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Search Results for: plaisant (187 matches)

Du, F., Plaisant, C., Spring, N., Shneiderman, B.
EventAction: Visual Analytics for Temporal Event Sequence Recommendation
To appear in Proceedings of the IEEE Visual Analytics Science and Technology (2016)
HCIL-2016-09

Recommender systems are being widely used to assist people in making decisions, for example, recommending films to watch or books to buy. Despite its ubiquity, the problem of presenting the recommendations of temporal event sequences has not been studied. We propose EventAction, which to our knowledge, is the first attempt at a prescriptive analytics interface designed to present and explain recommendations of temporal event sequences. EventAction provides a visual analytics approach to (1) identify similar records, (2) explore potential outcomes, (3) review recommended temporal event sequences that might help achieve the users' goals, and (4) interactively assist users as they define a personalized action plan associated with a probability of success. Following the design study framework, we designed and deployed EventAction in the context of student advising and reported on the evaluation with a student review manager and three graduate students.


 [Link to Report]

Chevalier, F., Riche, N., Plaisant, C., Chalbi, A., Hurter, C.
Animations 25 Years Later: New Roles and Opportunities
To appear in ACM Proc. of Advanced Visual Interfaces (2016)
HCIL-2016-07

Animations are commonplace in today's user interfaces. From bouncing icons that catch attention, to transitions helping with orientation, to tutorials, animations can serve numerous purposes. We revisit Baecker and Small's pioneering work Animation at the Interface, 25 years later. We reviewed academic publications and commercial systems, and interviewed 20 professionals of various backgrounds. Our insights led to an expanded set of roles played by animation in interfaces today for keeping in context, teaching, improving user experience, data encoding and visual discourse. We illustrate each role with examples from practice and research, discuss evaluation methods and point to opportunities for future research. This expanded description of roles aims at inspiring the HCI research community to find novel uses of animation, guide them towards evaluation and spark further research.


 [Link to Report]

Mauriello, M., Shneiderman, B., Du, F., Malik, S., Plaisant, C.
Simplifying Overviews of Temporal Event Sequences
Mauriello, M. L., Shneiderman, B., Du, F., Malik, S., Plaisant, C., Simplifying Overviews of Temporal Event Sequences, Extended Abstracts on Human Factors in Computing Systems, CHI '16 (2016) to appear
HCIL-2016-04

Beginning the analysis of new data is often difficult as modern datasets can be overwhelmingly large. With visual analytics in particular, displays of large datasets quickly become crowded and unclear. Through observing the practices of analysts working with the event sequence visualization tool EventFlow, we identified three techniques to reduce initial visual complexity by reducing the number of event categories resulting in a simplified overview. For novice users, we suggest an initial pair of event categories to display. For advanced users, we provide six ranking metrics and display all pairs in a ranked list. Finally, we present the Event Category Matrix (ECM), which simultaneously displays overviews of every event category pair. In this work, we report on the development of these techniques through two formative usability studies and the improvements made as a result. The goal of our work is to investigate strategies that help users overcome the challenges associated with initial visual complexity and to motivate the use of simplified overviews in temporal event sequence analysis.


 [Link to Report]

Onukwugha, E., Plaisant, C., Shneiderman, B.
Data Visualization Tools for Investigating Health Services Utilization Among Cancer Patients
In Hesse, B., Ahern, D., and Beckjord, E. (Eds.) Oncology Informatics, Elsevier (2016 to appear)
HCIL-2016-02

The era of "big data" promises more information for health practitioners, patients, researchers, and policy makers. For big data resources to be more than larger haystacks in which to find precious needles, stakeholders will have to aim higher than increasing computing power and producing faster, nimbler machines. We will have to develop tools for visualizing information; generating insight; and creating actionable, on-demand knowledge for clinical decision making. This chapter has three objectives: 1) to review the data visualization tools that are currently available and their use in oncology; 2) to discuss implications for research, practice, and decision making in oncology; and 3) to illustrate the possibilities for generating insight and actionable evidence using targeted case studies. A few innovative applications of data visualization are available from the clinical and research settings. We highlight some of these applications and discuss the implications for evidence generation and clinical practice. In addition, we develop two case studies to illustrate the possibilities for generating insight from the strategic application of data visualization tools where the interoperability problem is solved. Using linked cancer registry and Medicare claims data available from the National Cancer Institute, we illustrate how data visualization tools unlock insights from temporal event sequences represented in large, population-based datasets. We show that the information gained from the application of visualization tools such as EventFlow can define questions, refine measures, and formulate testable hypotheses for the investigation of cancer-related clinical and process outcomes.


 [Link to Report]

Bjarnadottir, M., Malik, S., Onukwugha, E., Gooden, T., Plaisant, C. (October 2015)
Understanding Adherence and Prescription Patterns Using Large Scale Claims Data
To appear in PharmacoEconomics
HCIL-2015-17

Purpose: Advanced computing capabilities and novel visual analytics tools now allow us to move beyond the traditional cross-sectional summaries to analyze longitudinal prescription patterns and the impact of study design decisions. For example, design decisions regarding gaps and overlaps in prescription fill data are necessary for measuring adherence using prescription claims data. However, little is known regarding the impact of these decisions on measures of medication possession (e.g., medication possession ratio). The goal of the study is to demonstrate the use of visualization tools for pattern discovery, hypothesis generation and study design.

Method: We utilize EventFlow, a novel discrete event sequence visualization software, to investigate patterns of prescription fills, including gaps and overlaps, utilizing large scale healthcare claims data. The study analyzes data of individuals who had at least two prescriptions for one of five hypertension medication classes: ACE inhibitors (ACE-I), Angiotensin II receptor blockers (ARB), Beta blockers (Beta), Calcium channel blockers (CCB) and Diuretics (Diur).

We focus on those members initiating therapy with Diuretics (19.2%) who may concurrently or subsequently take drugs in other classes as well. We identify longitudinal patterns in prescription fills for antihypertensive medications, investigate the implications of decisions regarding gap length and overlaps, and examine the impact on the average cost and adherence of the initial treatment episode.

Results: A total of 790,609 individuals are included in the study sample, 19.2% (N=151,566) of whom started on diuretics first during the study period. The average age is 52.4 years and 53.1% of the population is female. When the allowable gap is zero, 34% of the population has continuous coverage and the average length of continuous coverage is 2 months. In contrast, when the allowable gap is 30 days, 69% of the population shows a single continuous prescription period with an average length of 5 months. The average prescription cost of the period of continuous coverage ranges from $3.44 (when the maximum gap is 0 days) to $9.08 (when the maximum gap is 30 days). Results were less impactful when considering overlaps.

Conclusions: This proof-of-concept study illustrates the use of visual analytics tools in characterizing longitudinal medication possession. We find that prescription patterns and associated prescription costs are more influenced by allowable gap lengths than by definitions and treatment of overlap. Research using medication gaps and overlaps to define medication possession in prescription claims data should pay particular attention to the definition and use of gap lengths.


 [Link to Report]

Malik, S., Du, F., Plaisant, C., Bjarnadottir, M., Shneiderman, B. (April 2015)
High-Volume Hypothesis Testing: Systematic Exploration of Event Sequence Comparisons
To appear in ACM Transactions on Interactive Intelligent Systems (2015)
HCIL-2015-09

Cohort comparison studies have been traditionally hypothesis-driven and conducted with carefully controlled environment (such as clinical trials). Given two groups of event sequence data, researchers test a single hypothesis (e.g., does the group taking Medication A exhibit more deaths and earlier deaths than the group taking Medication B?). However, researchers are now moving towards more exploratory methods and retrospective analysis of existing data. High-Volume Hypothesis Testing (HVHT) becomes useful to compare datasets. Focusing on event sequences we propose new thechniques that provide context, effect, and flexibility during HVHT, and aid researchers in understanding HVHT results (how significant they are, why they are meaningful, and whether the entire dataset has been exhaustively explored). Using interviews and case studies with domain experts, we iteratively designed and implemented techniques dealing with prevalence, time, and frequency in a visual analytics tool, CoCo. These interaction techniques allow users to systematically and flexibly parse large result sets through filtering, searching, and journaling. We illustrate the utility of the method with a case study in the medical domain.


 [Link to Report]

Mauriello, M., Shneiderman, B., Du, F., Malik, S., Plaisant, C. (April 2015)
Simplified Overviews for Temporal Event Sequences: Designs for Novice and Expert Analysts
Contact plaisant@cs.umd.edu">Catherine Plaisant for a copy.
HCIL-2015-08

Simplified overviews enable novices to more easily begin data analysis and enable experts to see common and surprising patterns. Simplified overviews have been used in research and commercial software for multi-variate data by choosing two dimensions to show on a scatterplot. We bring this idea to temporal event sequences, by facilitating the selection of two event categories. This simple strategy was inspired by observations of our case study partners and appreciated by pilot study users. The design was extended to provide six metrics for selecting categories that simplified the overview to display. To address the need of expert users, we also present simplified overviews using a lower triangular matrix of small overviews with all pairs of event categories. Along with single event category overviews shown on the diagonal they provide a revealing overview of the dataset. We believe these simplified overviews help novice and expert analysts to more rapidly and successfully extract insights. The design is implemented in the EventFlow software and refined based on two usability studies with 5 and 6 users. As a result of our work, guidelines for the design of simplified overviews are proposed.


[Link to Report]

Du, F., Shneiderman, B., Plaisant, C., Malik, S., Perer, A. (April 2015)
Coping with Volume and Variety in Temporal Event Sequences: Strategies for Sharpening Analytic Focus
To appear in IEEE Transactions on Visualization and Computer Graphics (2016)
HCIL-2015-07

The growing volume and variety of data presents both opportunities and challenges for visual analytics. Addressing these challenges is needed for big data to provide valuable insights and novel solutions for business, security, social media, and healthcare. In the case of temporal event sequence analytics it is the number of events in the data and variety of temporal sequence patterns that challenges users of visual analytic tools. This paper describes 14 strategies for sharpening analytic focus that analysts can use to reduce the data volume and pattern variety. Four groups of strategies are proposed: (1) extraction strategies, (2) temporal folding, (3) pattern simplification strategies, and (4) iterative strategies. For each strategy we provide examples of use and of the impact of this strategy on volume and/or variety. Examples are selected from 18 case studies gathered from either our own work, the literature, or based on email interviews with application developers and analysts. Finally, we discuss how these strategies might be combined and opportunities for new technologies and user interfaces.


 [Link to Report]

Malik, S., Du, F., Monroe, M., Onukwugha, E., Plaisant, C., Shneiderman, B. (January 2015)
Cohort Comparison of Event Sequences with Balanced Integration of Visual Analytics and Statistics
In ACM Intelligent User Interfaces (IUI) 2015. Atlanta, GA, USA, 38-49. (2015)
DOI: 10.1145/2678025.2701407
HCIL-2015-02

Finding the differences and similarities between two datasets is a common analytics task. With temporal event sequence data, this task is complex because of the many ways single events and event sequences can differ between the two datasets (or cohorts) of records: the structure of the event sequences (e.g., event order, co-occurring events, or event frequencies), the attributes of events and records (e.g., patient gender), or metrics about the timestamps themselves (e.g., event duration). In exploratory analyses, running statistical tests to cover all cases is time-consuming and determining which results are significant becomes cumbersome. Current analytics tools for comparing groups of event sequences emphasize a purely statistical or purely visual approach for comparison. This paper presents a taxonomy of metrics for comparing cohorts of temporal event sequences, showing that the problem-space is bounded. We also present a visual analytics tool, CoCo (for "Cohort Comparison"), which implements balanced integration of automated statistics with an intelligent user interface to guide users to significant, distinguishing features between the cohorts. Lastly, we describe two early case studies: the first with a research team studying medical team performance in the emergency department and the second with pharmacy researchers.


 [Link to Report]

Guerra Gomez, J., Pack, M., Plaisant, C., Shneiderman, B. (January 2015)
Discovering temporal changes in hierarchical transportation data: Visual analytics & text reporting tools
To be published in the Transportation Research Part C: Emerging Technologies, Volume 51, February 2015 Pages 167-179
HCIL-2015-01

Analyzing important changes to massive transportation datasets like national bottleneck statistics, passenger data for domestic flights, airline maintenance budgets, or even publication data from the Transportation Research Record can be extremely complex. These types of datasets are often grouped by attributes in a tree structure hierarchy. The parent-child relationships of these hierarchical datasets allow for unique analytical opportunities, including the ability to track changes in the dataset at different levels of granularity, over time or between versions. For example, analysts can use hierarchies to uncover changes in the patterns of passengers flying in the United States over the last ten years, breaking down the data by states, cities, airports, and number of passengers. Exploring changes in travel patterns over time can help carriers make better decisions regarding their operations and long-range planning.

This paper describes TreeVersity2, a web-based data comparison tool that provides users with information visualization techniques to find what has changed in a dataset over time. TreeVersity2 enables users to explore data that can be inherently hierarchical or not (by categorizing them by their attributes). An interactive textual reporting tool complements the visual exploration when the amount of data is very large. The results of two case studies conducted with transportation domain experts along with the results of an exit questionnaire are also described. TreeVersity2 preloaded with several demo datasets can be found at http://treeversity.cattlab.umd.edu along with several example videos.


 [Link to Report]

Malik, S., Du, F., Monroe, M., Onukwugha, E., Plaisant, C., Shneiderman, B. (December 2014)
An Evaluation of Visual Analytics Approaches to Comparing Cohorts of Event Sequences
EHRVis Workshop on Visualizing Electronic Health Record Data, www.cs.umd.edu/hcil/parisehrvis, Paris (2014) 1-6
HCIL-2014-28

A common type of data analysis is finding the differences and similarities between two datasets. With temporal event sequence data, this task is complex because of the variety of ways single events and sequences of events can differ between the two groups (or cohorts) of records: the structure of the event sequences (e.g., event order, co-occurring events, or frequencies of events), the attributes about the events and records (e.g., gender of a patient), or metrics about the timestamps themselves (e.g., duration of an event). Running statistical tests to cover all these cases and determining which results are significant becomes cumbersome. Current visual analytics tools for comparing groups of event sequences emphasize a purely statistical or purely visual approach for comparison. In this paper, we present a novel visual analytics tool, CoCo (for "Cohort Comparison"), which balances automated statistics with user-driven analysis to guide users to significant, distinguishing features between the cohorts. We demonstrate the utility and impact of the visual analytics tool with a user study against a previous visualization-driven approach, EventFlow. For more information about CoCo, visit http://www.cs.umd.edu/hcil/coco.


 [Link to Report]

Shneiderman, B., Plaisant, C. (December 2014)
Sharpening Analytic Focus to Cope with Big Data Volume and Variety: Ten strategies for data focusing with temporal event sequences
IEEE Computer Graphics and Applications, 35, 3 (2015) 10-14
HCIL-2014-27

A growing number of visual analytic and statistical software tools are being built to deal with temporal event sequences. These tools often have difficulty in dealing with two problems: the volume of records (the number of records may grow to hundreds of millions, making it difficult to load or apply operations to the data) and the variety of patterns (longs records are unique and the variety makes it difficult to see global patterns such as relationships, clusters or gaps, as well as to identify errors or anomalies). We propose a taxonomy of analytic focusing strategies for temporal event sequences, based on our experience working with dozens of case studies using EventFlow. Most strategies can lead to reduction in volume and variety simultaneously.


 [Link to Report]

Plaisant, C., Monroe, M., Meyer, T., Shneiderman, B. (October 2014)
Interactive Visualization
Chapter 12 in Big Data and Health Analytics, Katherine Marconi and Harold Lehman (Eds), CRC Press - Taylor and Francis (2014), 243-262.
HCIL-2014-26

This chapter focuses on the central role of information visualization in health analytics. From the early x-rays to 3D volume visualizations rapid progress has been made, but the most exciting growth is now in the area of information visualization which offer interactive environments and analytic processes that help support exploration of EHR data, monitoring, or insight discovery. For example, a health organization might want to investigate patterns of drug prescriptions in patients with asthma, and compare prescribing practices with current guidelines. Temporal patterns are critical to this analysis, and interactive visualizations are beginning to support powerful temporal queries, present rich result summaries, and offer fluid interactions to identify the clinically relevant patterns hidden in the data. Visualization should soon help clinicians identify cohorts of patients who match selection criteria for clinical trials, or need to be brought back to the office. Visualization can also reveal data quality problems, which are common when repurposing clinical data for secondary analysis. After a quick summary of the state-of-the-art of information visualization systems for exploring and querying HER data, we describe in detail one recent system (EventFlow) developed by the Human-Computer Interaction Lab at the University of Maryland, and illustrate its use with an asthma prescription study example.


 [Link to Report]

Malik, S., Du, F., Monroe, M., Onukwugha, E., Plaisant, C., Shneiderman, B. (May 2014)
A Visual Analytics Approach to Comparing Cohorts of Event Sequences
ABSTRACT ONLY -- To receive a personal copy of the full paper under review, please contact plaisant@cs.umd.edu">Catherine Plaisant.
HCIL-2014-07

A common type of data analysis is finding the differences and similarities between two datasets. With temporal event sequence data, this task is complex because of the variety of ways single events and sequences of events can differ between the two groups (or cohorts) of records: the structure of the event sequences (e.g., event order, co-occurring events, or frequencies of events), the attributes about the events and records (e.g., gender of a patient), or metrics about the timestamps themselves (e.g., duration of an event). Running statistical tests to cover all these cases and determining which results are significant becomes cumbersome. Current visual analytics tools for comparing groups of event sequences emphasize a purely statistical or purely visual approach for comparison. In this paper, we describe a taxonomy of metrics for comparing cohorts of temporal event sequences, including sequence, time, and attribute metrics. We also present a visual analytics tool, CoCo (for "Cohort Comparison"), which balances automated statistics with user-driven analysis to guide users to significant, distinguishing features between the cohorts. Lastly, we demonstrate the utility and impact of the visual analytics tool with a user study.


[Link to Report]

Plaisant, C., Wu, J., Hettinger, A., Powsner, S., Shneiderman, B. (January 2014)
Novel User Interface Design for Medication Reconciliation: An Evaluation of Twinlist
In Journal of the American Medical Informatics Association 22, 2 (2015) 340-9.
HCIL-2014-02

Objective. The primary objective was to evaluate time, number of interface actions, and accuracy on medication reconciliation tasks using a novel user interface (Twinlist which lays out the medications in 5 columns based on similarity and uses animation to introduce the grouping) compared to a Baseline interface (where medications are presented side by side in 2 columns). To assess participant agreement with statements regarding clarity and utility and to elicit comparisons.

Material and Methods. A 1x2 within-subjects experimental design was used with interface (Twinlist or Baseline) as an independent variable and time, number of clicks, scrolls, and errors as dependent variables. Participants were practicing medical providers with experience performing medication reconciliation but no experience with Twinlist. They reconciled two cases in each interface (in a counterbalanced order), then provided feedback on the design of the interface.

Results. Twenty medical providers participated in the study for a total of 80 trials. The trials using Twinlist were statistically significantly faster (18%), with fewer clicks (40%) and scrolls (60%). Serious errors were noted 11 and 31 times in TwinList and Baseline trials respectively.

Discussion. Trials using Twinlist were faster and more accurate. Subjectively, participants rated Twinlist more favorably than Baseline. They valued the novel layout of the drugs but indicated that the included animation would be valuable for novices, but not necessarily for advanced users. Additional feedback from participants provides guidance for further development and clinical implementations.

Conclusions. Cognitive support of medication reconciliation through interface design can significantly improve performance and safety.


[Link to Report]

Franklin, L., Plaisant, C., Rahman, K., Shneiderman, B. (December 2013)
TreatmentExplorer: An Interactive Decision Aid for Medical Risk Communication and Treatment Exploration
to appear in Interacting with Computers
HCIL-2013-32

Medical treatments carry unique benefits and risks which patients must understand in order to decide which option is best for them. Prior research has demonstrated that patients are ill-equipped to understand the statistical information presented to them through standard decision aids. We describe a prototype decision aid, TreatmentExplorer, which supports patients' needs by presenting treatment outcome, onset of symptoms, and treatment side effects using a novel graphic representation with staged animation and text-only narration. Our prototype also illustrates the use of a data driven personalization approach by using electronic health record data. We report on expert reviews, a pilot study (n=24) and a main study (n=42), which characterize the benefits of TreatmentExplorer over a text-only decision aid as well as a version without staged animation, and conclude with guidelines for designers.


 [Link to Report]

Carter, E., Burd, R., Monroe, M., Plaisant, C., Shneiderman, B. (October 2013)
Using EventFlow to Analyze Task Performance During Trauma Resuscitation
Proc. of the Workshop on Interactive Systems in Healthcare, WISH2013 (2013)
HCIL-2013-19

The Advanced Trauma Life Support (ATLS) protocol provides trauma teams with a framework for the initial evaluation and treatment of injured patients. The objective of this study was to analyze patterns of ATLS task performance among trauma resuscitation teams. EventFlow was useful for analyzing our dataset that contained multiple time-stamped variables and interval data. Deviations from ATLS protocol were easy to detect and the align function allowed for quick identification of various types of protocol violations.


 [Link to Report]

Franklin, L., Plaisant, C., Shneiderman, B. (July 2013)
An Information-Centric Framework for Designing Patient-Centered Medical Decision Aids and Risk Communication
In Proc. of AMIA 2013, 456-465.
HCIL-2013-15

Risk communication is a major challenge in productive patient-physician communication. Patient decision making responsibilities coms with an implicit assumption that patients are sufficiently educated and confident in their abilities to make decisions about their care based on evidence based treatment recommendations. Attempts to improve health literacy in patients by way of graphical decision aids have met with success. Such decision aids typically have been designed for a general population and evaluated based on whether or not users of the decision aid can accurately report the data points in isolation. To classify decision aids, we present an information-centric framework for assessing the content delivered to patients. We provide examples of our framework from a literature survey and suggest ways improvements can be made by considering all dimensions of our framework.


 [Link to Report]

Monroe, M., Meyer, T., Plaisant, C., Lan, R., Wongsuphasawat, K., Coster, T., Gold, S., Millstein, J., Shneiderman, B. (June 2013)
A Pilot Study of Asthma Medications in the Military Health System
A shortened version appears as Meyer, T., Monroe, M., Plaisant, C., Lan, R., Wongsuphasawat, K., Coster, T., Gold, S., Millstein, J., Shneiderman, B., Visualizing Patterns of Drug Prescriptions with EventFlow: A Pilot Study of Asthma Medications in the Military Health System, Proc. Of Workshop on Visual Analytics in HealthCare, VAHC2013 - Copyright retained by the authors (2013)
HCIL-2013-13

The Food and Drug Administration and Department of Defense were interested in detecting sub-optimal use of long-acting beta-agonists (LABAs) in asthmatics within the Military Health System (MHS). Visualizing the patterns of asthma medication use surrounding a LABA prescription is a quick way to detect possible sub-optimal use for further evaluation. The US Army, Office of the Surgeon General, Pharmacovigilance Center (PVC) selected a random sample of 100 asthma patients under age 65 with a new LABA prescription from January 1, 2006-March 1, 2010 in MHS healthcare claims. Analysis was conducted in EventFlow, a novel interactive visualization tool being developed by the University of Maryland Human Computer Interaction Lab (HCIL) to display and summarize time-point and interval data. EventFlow groups individuals that share the same sequence of medications and displays the average interval times between events. We found that EventFlow was effective in uncovering clinically relevant patterns in the data. Epidemiologists reported that EventFlow was a powerful tool for rapidly visualizing possible patterns of sub-optimal LABA use that can be targeted for intervention.


 [Link to Report]

Monroe, M., Lan, R., Plaisant, C., Shneiderman, B. (May 2013)
Temporal Event Sequence Simplification
In IEEE Trans. Visualization and Computer Graphics, 19, 12 (2013), 2227-36.
HCIL-2013-11

Electronic Health Records (EHRs) have emerged as a cost-effective data source for conducting medical research. The difficulty in using EHRs for research purposes, however, is that both patient selection and record analysis must be conducted across very large, and typically very noisy datasets. Our previous work introduced EventFlow, a visualization tool that transforms an entire dataset of temporal event records into an aggregated display, allowing researchers to analyze population-level patterns and trends. As datasets become larger and more varied, however, it becomes increasingly difficult to provide a succinct, summarizing display. This paper presents a series of user-driven data simplifications that allow researchers to pare event records down to their core elements. Furthermore, we present a novel metric for measuring visual complexity, and a language for codifying disjoint strategies into an overarching simplification framework. These simplifications were used by real-world researchers to gain new and valuable insights from initially overwhelming datasets.


 [Link to Report]

Lan, R., Lee, H., Monroe, M., Fong, A., Plaisant, C., Shneiderman, B. (May 2013)
Temporal Search and Replace: An Interactive Tool for the Analysis of Temporal Event Sequences
Monroe, M., Lan, R., Lee, H., Fong, A., Plaisant, C., Powsner, S., Shneiderman, B., Temporal Search and Replace: A Graphic-Based Solution to Temporal Event Data Wrangling and Incremental Querying, Proc. of Workshop on Visual Analytics in HealthCare, VAHC2013 - Copyright retained by the authors (2013)
HCIL-2013-10

Visualization of temporal event data is increasingly important for the analysis of a broad range of data including electronic health records, web logs, and financial data. In many analytic tasks, users need the capability to manipulate the data to reveal patterns and make insights. To support this analytic need, we introduce a novel temporal search and replace tool (TSR) implemented in our existing EventFlow visual analytic system to facilitate visual-language-based search and replacement of temporal event sequences. We also introduce two types of search constraints: repetition and permutation that integrate regular expression concepts into temporal event sequence searching. We present the replacement strategy for event sequences under these constraints. Example use cases are discussed where TSR solves problems both on temporal event data analysis and simplification. Finally we report on a usability study with 10 participants.


 [Link to Report]

Plaisant, C., Chao, T., Wu, J., Hettinger, A., Herskovic, J., Johnson, T., Bernstam, E., Markowitz, E., Powsner, S., Shneiderman, B. (May 2013)
Twinlist: Novel User Interface Designs for Medication Reconciliation
In Proc. of AMIA 2013, 1150-1159.
HCIL-2013-09

Medication reconciliation is an important and complex task for which careful user interface design has the potential to help reduce errors and improve quality of care. In this paper we focus on the hospital discharge scenario and first describe a novel interface called Twinlist. Twinlist illustrates the novel use of spatial layout combined with multi-step animation, to help medical providers see what is different and what is similar between the lists (e.g. intake list and hospital list), and rapidly choose the drugs they want to include in the reconciled list. We then describe a series of variant designs and discuss their comparative advantages and disadvantages. Finally we report on a pilot study that suggests that animation might help users learn new spatial layouts such as the one used in Twinlist.


 [Link to Report]

Sopan, A., Plaisant, C., Powsner, S., Shneiderman, B. (May 2013)
Reducing Wrong Patient Selection Errors: Exploring the Design Space of User Interface Techniques
Proc. AMIA 2014 Annual Symposium, 1056-65
HCIL-2013-07

Wrong patient selection errors are a major issue for patient safety; from ordering medication to performing surgery, the stakes are high. Widespread adoption of Electronic Health Record (EHR) and Computerized Provider Order Entry (CPOE) systems makes patient selection using a computer screen a frequent task for clinicians. Careful design of the user interface can help mitigate the problem by helping providers recall their patients' identities, accurately select their names, and spot errors before orders are submitted. We propose a catalog of twenty seven distinct user interface techniques, organized according to a task analysis. An associated video demonstrates eighteen of those techniques. HER designers who consider a wider range of human-computer interaction techniques could reduce selection errors, but verification of efficacy is still needed.

Project webpage with video demonstration: http://www.cs.umd.edu/hcil/WPE/


 [Link to Report]

Guerra Gomez, J., Pack, M., Plaisant, C., Shneiderman, B. (May 2013)
Visualizing changes over time in datasets using dynamic hierarchies
Published in IEEE Trans. Visualization and Computer Graphics, 19, 12 (2013), 2566-75
HCIL-2013-06

To analyze datasets like the US Federal Budget or the number of students in a University it is common to look for changes over time. This task can be easier and more fruitful if the analysis is performed by grouping by attributes, such as by Agencies, Bureaus and Accounts for the Budget or by Ethnicity, Gender and Major in a University. We present TreeVersity2, a web based interactive data visualization tool that allows users to analyze changes in datasets by creating dynamic hierarchies based on the data attributes. TreeVersity2 introduces a novel space filling visualization designed to represent changes in trees, that showcase the change on all tree levels, not only the leaves. With this visualization users can explore absolute and relative changes, created and removed nodes, and each node’s actual values, while maintaining the context. Moreover, TreeVersity2 includes time-based visualizations that provide the context of the each node’s change over time. Finally, TreeVersity2 provides a reporting tool that lists outliers in textual form, which can help users identify what has changed in the data without having to manually setup the filters. We validated TreeVersity2 with 12 case studies with organizations as diverse as the National Cancer Institute, Federal Drug Administration, Department of Transportation, Office of the Bursar of the University of Maryland, and even eBay. Our case studies demonstrated that TreeVersity2 is flexible enough to be used in different domains to reveal useful insights for the data owners. A demo of TreeVersity2 can be seen at https://treeversity.cattlab.umd.edu.


 [Link to Report]

Shneiderman, B., Plaisant, C., Hesse, B. (January 2013)
Improving health and healthcare with interactive visualization methods
IEEE Computer, Special Issue on Challenges in Information Visualization, 46, 5 (2013) 58-66
HCIL-2013-01

Interactive information visualization and visual analytics methods will bring profound changes to personal health programs, clinical healthcare delivery, and public health policy making. This article describes the state of the art within these three domains and gives examples of current efforts that hint at the remarkable transformations that are possible. Then it offers seven challenges for information visualization and visual analytics researchers. The arguments and challenges are aligned with the National Institutes of Health’s roadmap for Predictive, Preemptive, Personalized, and Participative medicine. Many technologies need substantial advances to produce reliable, effective, safe, and validated systems, but the potential societal benefits are enormous.


 [Link to Report]

Monroe, M., Lan, R., Morales del Olmo, J., Shneiderman, B., Plaisant, C., Millstein, J. (October 2012)
The Challenges of Specifying Intervals and Absences in Temporal Queries: A Graphical Language Approach
Published in Proc. Of ACM Conference on Human-Computer Interaction (CHI 2013), 2349-2358.
HCIL-2012-30

In our burgeoning world of ubiquitous sensors and affordable data storage, records of timestamped events are being produced across nearly every domain of personal and professional computing. This data ranges from government-funded medical databases, to the meticulously tabulated comings and goings of obsessive self-trackers. Across all domains, however, is the need to search these records for meaningful patterns of events. This paper reports on a two-part user study, as well as a series of early tests and interviews with clinical researchers, that informed the development of two temporal query interfaces: a basic, menu-based interface and an advanced, graphic-based interface. While the scope of temporal query is very broad, this work focuses on two particularly complex and critical facets of temporal event sequences: intervals (events with both a start time and an end time), and the absence of an event. We describe how uses encounter a common set of difficulties when expressing such queries, and propose solutions to help overcome them. Finally, we report on 2 case studies with epidemiologists at the US Army Pharmacovigilance Center, illustrating how both query interfaces were used to study patterns of drug use.


 [Link to Report]

Pantazos, K., Tarkan, S., Plaisant, C., Shneiderman, B. (September 2012)
Exposing Delays in Multi-Step Processes by Retrospective Analysis
HCIL-2012-27

Multi-step processes are common in healthcare, software development, and other dynamic environments. Managers who monitor processes are overwhelmed by information, and have limited time to investigate data from different viewpoints. We propose the interactive Multi-Step Process Visualization (MSProVis) for retrospective analysis, to expose delays in multi-step processes, and support the comparisons between steps or between actors executing those steps. A usability study with seven users showed that all participants could use MSProVis effectively and rapidly gain insights.


 [Link to Report]

Lam, H., Bertini, E., Isenberg, P., Plaisant, C., Carpendale, S. (September 2012)
Empirical Studies in Information Visualization: Seven Scenarios
Published in: IEEE Transactions on Visualization and Computer Graphics, 18, 9 (2012) 1520-1536
HCIL-2012-26

We take a new, scenario-based look at evaluation in information visualization. Our seven scenarios, evaluating visual data analysis and reasoning, evaluating user performance, evaluating user experience, evaluating environments and work practices, evaluating communication through visualization, evaluating visualization algorithms, and evaluating collaborative data analysis were derived through an extensive literature review of over 800 visualization publications. These scenarios distinguish different study goals and types of research questions and are illustrated through example studies. Through this broad survey and the distillation of these scenarios, we make two contributions. One, we encapsulate the current practices in the information visualization research community and, two, we provide a different approach to reaching decisions about what might be the most effective evaluation of a given information visualization. Scenarios can be used to choose appropriate research questions and goals and the provided examples can be consulted for guidance on how to design one's own study.


[Link to Report]

Tarkan, S., Franklin, L., Plaisant, C., Shneiderman, B. (September 2012)
Design Guidelines for Ensuring Timely Management of Medical Orders
In Zhang J, Walji M, eds. Better EHR: usability, workflow & cognitive support in electronic health records. Houston, TX: University of Texas School of Biomedical Informatics; 2014. p. 239-247.
HCIL-2012-25

Medical professionals need to handle the orders for their patients. Many steps can go wrong in the result management process and current systems fail to solve the missed results problem. We introduce our design guidelines for rich tabular displays to ensure timely medical care: (i) show pending results, (ii) prioritize by late and lost status, (iii) clarify responsibility, and (iv) embed actions. We evaluated the benefits of applying the first two guidelines in a user study, which showed very promising results. These guidelines can be applied to a variety of other application domains.


 [Link to Report]

Plaisant, C., Chao, T., Liu, R., Norman, K., Shneiderman, B. (September 2012)
Multi-Step Animation to Facilitate the Understanding of Spatial Groupings: the Case of List Comparisons
HCIL-2012-23

While animation has been shown to be compelling and helpful to reveal transformations of complex graphical representations such as trees or graphs, other studies have cast doubts on animation’s usefulness for learning. We present a new beneficial use of animation: helping users learn and understand the meaning of the spatial grouping of items on the screen. We introduce this technique in the design of two list comparison interfaces: Twinlist, an interface that helps physicians compare and merge two separate lists of medications into a reconciled list; and ManyLists, an interface for product comparison. Animation is used to reveal the similarities and differences between items in the lists and explain the final grouping. A controlled experiment confirmed that animation helped participants learn the groupings of Twinlist. Finally we summarize design guidelines and discuss other possible uses of the technique.


 [Link to Report]

Guerra Gomez, J., Buck-Coleman, A., Pack, M., Plaisant, C., Shneiderman, B. (August 2012)
TreeVersity: Interactive Visualizations for Comparing Hierarchical Datasets
Transportation Research Record (TRR), Journal of the Transportation Research Board (2013) -- 21 pages ** Received the Greg Herrington Award from the National Academy of Sciences Transportation Research Board (TRB) for Excellence in Visualization Research.
HCIL-2012-14

Transportation datasets of all kinds are hierarchical in nature, and therefore easily represented in tree structures. Visually comparing the changes in these hierarchical datasets over time can be extremely difficult, even when the trees are relatively small. TreeVersity is a novel interactive visualization that allows users to detect and analyze changes in the structure and value of various components of the tree. TreeVersity uses dual comparison techniques (side-by-side and explicit differences) coupled with a tabular representation to help users understand and explore changes to the tree over time. It uses carefully selected color palettes to show positive/negative, absolute and relative value changes; and glyphs that preattentively show these changes. This paper illustrates the value of this visualization through several short case studies using Federal transportation budget data, airline maintenance budgets, transportation publication data, and hypothesizes about TreeVersity’ s relevance for future congestion trend analysis. Video demonstrations of this research can be viewed at http://tinyurl.com/treeversity.


 [Link to Report]

Ahn, J., Plaisant, C., Shneiderman, B. (June 2012)
A Task Taxonomy for Network Evolution Analysis
Revised version appeared in IEEE Transactions on Visualization and Computer Graphics, 20, 3 (2014) 365-376
HCIL-2012-13

Visualization has proven to be a useful tool for understanding network structures. However the dynamic nature of social media networks requires powerful visualization techniques that go beyond static network diagrams. In order to provide strong temporal network visualization tools, designers need to understand what tasks that users have to accomplish. This paper describes a taxonomy of temporal network visualization tasks. We identify the (1) entities, (2) properties, and (3) a hierarchy of temporal features, which were extracted by surveying 44 existing temporal network visualization systems. By building and examining the task taxonomy, we report which tasks are well covered by existing systems and make suggestions for designing future visualization tools. The feedback from 9 network analysts helped refine the taxonomy.


 [Link to Report]

Liu, R., Chao, T., Plaisant, C., Shneiderman, B. (April 2012)
ManyLists : Product Comparison Tool Using Spatial Layouts with Animated Transitions
HCIL-2012-10

Product comparison is a common process consumers perform every day. However, current tools provide limited functions and poor visual designs. We present ManyLists, a product comparison tool that compares products’ features using Spatial Layouts with Animated Transitions. In addition colorcoding is used to highlight the best features among the products. A usability study with fourteen participants provided evidence that the visualization is easy to learn and the animated transitions are helpful. Finally we propose three guidelines for Spatial Layouts with Animated Transitions: break multi-step processes into small comprehensible steps, show animated transitions for each step, and use spatial layouts to indicate relationships among features.


 [Link to Report]

Pantazos, K., Tarkan, S., Plaisant, C., Shneiderman, B. (April 2012)
Promoting Timely Completion of Multi-Step Processes - A Visual Approach to Retrospective Analysis
HCIL-2012-09

Multi-step processes are common in healthcare, software development, and other dynamic environments. Managers who monitor processes are overwhelmed by information, and often limited in the time to investigate data from different viewpoints. We propose a visual approach to facilitate retrospective analysis, to promote timely completion of multi-step processes, and improve performance. It uses a novel visualization called the Process Completion Diagram (PCD) that aggregates event-logs into in-time, late and not-completed completions, and visualizes those using shapes and colors. The interactive Multi-Step Process Visualization (MSPro- Vis) combines a number of PCDs and allows users to review and compare series of PCDs at three levels of detail, allowing comparisons between steps or between actors executing those steps. MSProVis computes default thresholds that define in-time and late completions. These might trigger alarms, and allow managers to adjust those thresholds interactively.

A pilot usability test with five participants showed that all participants could learn how to read almost all the information presented in the PCD without training in less than five minutes, and use MSProVis effectively. They carried out nine tasks successfully, which lasted on average seven minutes. Suggestions for improvement include color usage, and label and shape positioning.

Index Terms: Visual Analytics, Process Completion Diagram, Multi-Step Process Visualization.


 [Video] [Link to Report]

Tao, C., Wongsuphasawat, K., Clark, K., Plaisant, C., Chute, C. (April 2012)
Towards Event Sequence Representation, Reasoning and Visualization for HER Data
Published in: Proc. 2nd ACM International Health Informatics Symposium, ACM Press, New York (2012), 801-805.
HCIL-2012-07

Efficient analysis of event sequences and the ability to answer time-related, clinically important questions can accelerate clinical research in several areas such as causality assessments, decision support systems, and retrospective studies. The Clinical Narrative Temporal Reasoning Ontology (CNTRO)-based system is designed for semantically representing, annotating, and inferring temporal relations and constraints for clincial events in Electronic Health Records (EHR) represented in both structured and unstructured ways. The LifeFlow system is designed to support an interactive exploration of event sequences using visualization techniques. The combination of the two systems will provide a comprehensive environment for users to visualize inferred temporal relationships from EHR data. This paper discusses our preliminary efforts on connecting the two systems and the benefits we envision from such an environment.


 [Link to Report]

Monroe, M., Wongsuphasawat, K., Plaisant, C., Shneiderman, B., Millstein, J., Gold, S. (April 2012)
Exploring Point and Interval Event Patterns: Display Methods and Interactive Visual Query
HCIL-2012-06

Our work on searching point-based event sequences with the Align, Rank, Filter, and Summary concepts produced a powerful tool (Lifelines2) that is being applied in an increasing set of medical and other applications. The LifeFlow aggregation tool expanded the capabilities of Lifelines2 to show common patterns of events on a single-screen display, resulting in the ability to summarize millions of individual patient records. However, users found that point-based event sequences limited their capacity to solve problems that had inherently interval attributes, for example, the 3-month interval during which patients took a medication. This paper reports on our development of EventFlow, an application that integrates interval-based events into the original LifeFlow mechanisms. Interval events represent a fundamental increase in complexity at every level of the application, from the input and data structure to the eventual questions that a user might ask of the data. Our goal was to accomplish this integration in a way that appeared to users as a simple and intuitive extension of the original LifeFlow tool. In this paper, we present novel solutions for displaying interval events, simplifying their visual impact, and incorporating them into meaningful queries.


 [Video] [Link to Report]

Cheng, H., Plaisant, C., Shneiderman, B. (April 2012)
Identifying and Measuring Associations of Temporal Events
HCIL-2012-05

Large databases of temporal records have made it possible for researchers to verify their hypotheses related to temporal event sequences. However, with the overwhelming size of data and numerous possible patterns, an important issue is what patterns should be highlighted and presented to users. We implement a visualization tool, PairFinder, to enable users to efficiently locate patterns of interest. Users can 1) see all the results of the potential event patterns and 2) use interestingness measures to rank event patterns by their interestingness. In addition, users can hide irrelevant patterns and filter records by record attributes. By looking only at the topranked patterns, users can easily scan large number of patterns. We demonstrate the potential of PairFinder with four case studies and summarize the patterns found in the data sets.


 [Video] [Link to Report]

Guerra Gomez, J., Buck-Coleman, A., Plaisant, C., Shneiderman, B. (April 2012)
TreeVersity: Interactive Visualizations for Comparing Two Trees with Structure and Node Value Changes
Proc. Conference of the Design Research Society - DRS2012 (2012) 1-10
HCIL-2012-04

When comparing two trees, the most common tasks are to identify changes in the node values and to identify topological differences. However even in trees with just a dozen nodes it is difficult to see those differences. TreeVersity is a novel interactive visualization that allows users to detect both node value changes and topological differences. TreeVersity uses dual comparison techniques (side-by-side and explicit differences) coupled with a tabular representation, to help users understand and explore the differences. It uses carefully-designed color palettes to show positive/negative, absolute, and relative value changes; and glyphs that preattentively show these changes and also highlight created and removed nodes. To illustrate the use of TreeVersity we compared 1) the 2012 and 2013 U.S. Federal Budget and 2) airlines’ maintenance budgets. In a usability test all eight participants were able to identify differences between trees without training and suggested improvements which were implemented. TreeVersity was also applied in a Facebook app called MySocialTree to navigate the news feed as a tree of friends. A survey of 15 users of MySocialTree suggested that they were able to understand and navigate TreeVersity’s glyphs and found it useful.


 [Link to Report]

Chao, T., Plaisant, C., Shneiderman, B. (January 2012)
Twinlist: Overview and general implementation description
HCIL-2012-03

Medication reconciliation can help prevent adverse health outcomes, but the process is nontrivial. Here we focus on the user interface that clinicians might use to compare and merge two separate lists of medications. Similarities and differences between the lists need to be identified; decisions need to be made as to which medications should be continued and which ones should be stopped. We describe a novel prototype called Twinlist that uses animation and spatial layout to reveal similarities, and simple interactive controls to facilitate "accept" or "reject" decisions. We also suggest extensions and modifications that may be useful for widespread adoption (provided as "notes" in a smaller font size).

Twinlist was designed as an inspirational standalone prototype. If adopted, it would become part of the user interface of a larger system (e.g. a CPOE or EHR system). Here we will refer to that interface as the "outer" interface.

This document assumes that the reader is already familiar with Twinlist's video demonstration.


 [Link to Report]

Sopan, A., Rey, P., Ahn, J., Plaisant, C., Shneiderman, B. (February 2012)
The Dynamics of Web-Based Community Safety Groups: Lessons Learned from the Nation of Neighbors
Published in Signal Processing Magazine, IEEE volume 30, issue 6, 157-162.
HCIL-2012-02

Community safety as a social issue has expanded its reach to web forums, portals and dedicated sites. This paper presents our study of 230 community safety groups whose members communicate through the Nation of Neighbors website. We analyze the patterns of activities within these communities along with their temporal dynamics. We demonstrate both feature-based and temporal analyses of the communities aiming at discovering the characteristics that make such communities successful. We use ManyNets’s capability to visualize the overview of multiple networks at once, demonstrating the value of visual analytics for community managers to better understand their communities. Using previously-developed health metrics we distinguish the successful communities, observe the influence of leaders in those communities and establish that larger communities are reporting more crime incidents rather than having discussion on other topics. To our surprise, we did not observe any strong association between the involvement of Law Enforcement personnel and activeness of the communities.


 [Link to Report]

Kandel, S., Heer, J., Plaisant, C., Kennedy, J., Ham, F., Riche, H., Weaver, C., Lee, B., Brodbeck, D., Buono, P. (October 2011)
Research Directions in Data Wrangling: Visualizations and Transformations for Usable and Credible Data
Published in: Information Visualization, 10, 4 (2011) 271-288
HCIL-2011-34

In spite of advances in technologies for working with data, analysts still spend an inordinate amount of time diagnosing data quality issues and manipulating data into a usable form. This process of 'data wrangling' often constitutes the most tedious and time-consuming aspect of analysis. Though data cleaning and integration are longstanding issues in the database community, relatively little research has explored how interactive visualization can advance the state of the art. In this article, we review the challenges and opportunities associated with addressing data quality issues. We argue that analysts might more effectively wrangle data through new interactive systems that integrate data verification, transformation, and visualization. We identify a number of outstanding research questions, including how appropriate visual encodings can facilitate apprehension of missing data, discrepant values, and uncertainty; how interactive visualizations might facilitate data transform specification; and how recorded provenance and social interaction might enable wider reuse, verification, and modification of data transformations.


 [Link to Report]

Lam, H., Bertini, E., Isenberg, P., Plaisant, C., Carpendale, S. (December 2011)
Empirical Studies in Information Visualization: Seven Scenarios
Published in: IEEE Transactions on Visualization and Computer Graphics, 30 Nov. 2011. IEEE computer Society Digital Library. IEEE Computer Society, http://doi.ieeecomputersociety.org/10.1109/TVCG.2011.279
HCIL-2011-31

We take a new, scenario based look at evaluation in information visualization. Our seven scenarios, evaluating visual data analysis and reasoning, evaluating user performance, evaluating user experience, evaluating environments and work practices, evaluating communication through visualization, evaluating visualization algorithms, and evaluating collaborative data analysis were derived through an extensive literature review of over 800 visualization publications. These scenarios distinguish different study goals and types of research questions and are illustrated through example studies. Through this broad survey and the distillation of these scenarios we make two contributions. One, we encapsulate the current practices in the information visualization research community and, two, we provide a different approach to reaching decisions about what might be the most effective evaluation of a given information visualization. Scenarios can be used to choose appropriate research questions and goals and the provided examples can be consulted for guidance on how to design one's own study.


[Link to Report]

Guerra Gomez, J., Buck-Coleman, A., Plaisant, C., Shneiderman, B. (October 2011)
Interactive Visualizations for Comparing Two Trees With Structure and Node Value Changes
HCIL-2011-22

A common data analysis task is to compare pairs of trees to detect changes in leaf or interior node values and to identify created and removed nodes. However even in trees with just a dozen nodes it is difficult to find those differences. We present TreeVersity, a new interactive visualization that gives users powerful tools to detect both node value changes and topological differences. TreeVersity uses dual comparison techniques (side-by-side and explicit differences) and tabular representations, to facilitate the understanding and navigation of the differences. TreeVersity's design employs carefullydesigned color palettes to show positive/negative, absolute, and relative value changes; shapes that preattentively show these changes; and novel graphical approaches that highlight created and removed nodes. We illustrate TreeVersity's functionality through comparison of the 2011 and 2012 U.S. Federal Budget. Eight usability test participants, with no initial training, identified many differences between the two trees, while suggesting improvements which were implemented.


 [Link to Report]

Claudino, L., Khamis, S., Liu, R., London, B., Pujara, J., Plaisant, C., Shneiderman, B. (September 2011)
Facilitating Medication Reconciliation with Animation and Spatial layout
In Proceedings of the Workshop on Interactive Healthcare Systems (WISH2011), 1-4.
HCIL-2011-20

Our project looks at novel user interfaces to facilitate medication reconciliation. We are focusing on the user interface that physicians might use to compare and merge two separate lists of medications. Similarities and differences between the lists need to be identified; decisions need to be made as to which medications should be continued and which ones should be stopped. We describe a novel prototype called TwinList that uses animation and spatial layout to reveal similarities, and color to highlight differences in similar medications. Simple interactive controls facilitate the selection of sets of medications to be continued or stopped. We are in the early stages of user evaluation.


 [Link to Report]

Tarkan, S., Plaisant, C., Shneiderman, B., Hettinger, A. (July 2011)
Ensuring Timely Clinical Lab Test Result Management: A Generative XML Process Model to Support Medical Care
HCIL-2011-15

This paper presents the innovative design and implementation of MSTART (Multi-Step Task Alerting, Reminding, and Tracking), which uses XML specifications of a workflow model. This model specifies a hierarchy of process definitions, which when combined with a database of actors and organizations, provides input for an Interface Generator. This novel software architecture produces a domain independent system that can be widely used and easily modified to generate MSTART applications for business, academic, or other processes. Our focus in this paper is on handling medical laboratory tests to reduce the currently dangerous number of missed laboratory reports. This paper expands on our initial work [31] by describing three approaches to improve test processes so as to ensure that results are returned and acted on: (1) a refined workflow definition of agent temporal responsibilities to model more complex processes, (2) a strategy to generate actor action sheets that offer appropriate choices at each step, and (3) a configuration file mechanism to more accurately predict process result times. While our examples are tied to medical laboratory tests, our design supports many multistep processes.


 [Link to Report]

Ahn, J., Plaisant, C., Shneiderman, B. (April 2011)
A Task Taxonomy of Network Evolution Analysis
HCIL-2011-09

Visualization is a useful tool for understanding the nature of networks. The recent growth of social media requires more powerful visualization techniques beyond static network diagrams. One of the most important challenges is the visualization of temporal network evolution. In order to provide strong temporal visualization methods, we need to understand what tasks users accomplish. This study provides a taxonomy of the temporal network visualization tasks. We identify (1) the entities, (2) the properties to be visualized, and (3) the hierarchy of temporal features, which were extracted by surveying existing temporal network visualization systems. By building and examining the task taxonomy, we report which tasks have been covered so far and suggest additions for designing the future visualizations. We also present example visualizations constructed using the task taxonomy for a social networking site in order to validate the quality of the taxonomy.


 [Link to Report]

Markowitz, E., Bernstam, E., Herskovic, J., Zhang, J., Shneiderman, B., Plaisant, C., Johnson, T. (April 2011)
Medication Reconciliation: Work Domain Ontology, Prototype Development, and a Predictive Model
Published in: AMIA Annual Symp Proc. (2011) 878-87
HCIL-2011-07

Medication errors can result from administration inaccuracies at any point of care and are a major cause for concern. To develop a successful MR tool, we believe it necessary to build a Work Domain Ontology (WDO) for the MR process. A WDO defines the explicit, abstract, implementation-independent description of the task by separating the task from work context, application technology, and cognitive architecture. We developed a prototype based upon the WDO and designed to adhere to standard principles of interface design. The prototype was compared to Legacy Health System’s and PAML Builder MR tools via a KLM analysis for three MR tasks. The analysis found the prototype requires the fewest mental operations, completes tasks in the fewest steps, and completes tasks in the least amount of time. Accordingly, we believe that developing a MR tool, based upon the WDO and user interface guidelines, improves user efficiency and reduces cognitive load.


 [Link to Report]

Tarkan, S., Plaisant, C., Shneiderman, B., Hettinger, A. (March 2011)
Reducing Missed Laboratory Results: Defining Temporal Responsibility, Generating User Interfaces for Test Process Tracking, and Retrospective Analyses to Identify Problems
Published in American Medical Informatics Association 2011 Annual Symposium Proceedings.
HCIL-2011-06

Researchers have conducted numerous case studies reporting the details on how laboratory test results of patients were missed by the ordering medical providers. Given the importance of timely test results in an outpatient setting, there is limited discussion of electronic versions of test result management tools to help clinicians and medical staff with this complex process. This paper presents three ideas to reduce missed results with a system that facilitates tracking laboratory tests from order to completion as well as during follow-up: (1) define a workflow management model that clarifies responsible agents and associated time frame, (2) generate a user interface for tracking that could eventually be integrated into current electronic health record (HER) systems, (3) help identify common problems in past orders through retrospective analyses.


 [Link to Report]

Wang, T., Wongsuphasawat, K., Plaisant, C., Shneiderman, B. (January 2011)
Extracting Insights from Electronic Health Records: Case Studies, a Visual Analytics Process Model, and Design Recommendations
Published in Journal of Medical Systems (2011) PMID 21541691.
HCIL-2011-01

Current electronic health record (EHR) systems facilitate the storage, retrieval, persistence, and sharing of patient data. However, the way physicians interact with EHRs has not changed much. More specifically, support for temporal analysis of a large number of EHRs has been lacking. A number of information visualization techniques have been proposed to alleviate this problem. Unfortunately, due to their limited application to a single case study, the results are often difficult to generalize across medical scenarios. We present the usage data of Lifelines2 [22], our information visualization system, and user comments, both collected over eight different medical case studies. We generalize our experience into a visual analytics process model for multiple EHRs. Based on our analysis, we make seven design recommendations to information visualization tools to explore EHR systems.


 [Link to Report]

Ho, P., Wang, T., Wongsuphasawat, K., Plaisant, C., Shneiderman, B., Smith, M., Roseman, D. (December 2010)
Monitoring and Improving Quality of Care with Interactive Exploration of Temporal Patterns in Electronic Health Records
HCIL-2010-32

As the use of electronic health records (EHRs) spreads, interactive query interfaces will assist researchers and clinicians to quickly find historical records that include specific temporal patterns. This paper describes such an interface called LifeLines2, and summarizes how it was applied to a set of clinical problems. Our experience indicates that LifeLines2 was helpful to: 1) quickly identify unknown data quality issues, 2) speed up the finding of patients exhibiting specific temporal patterns of interest, 3) allow repeated queries to facilitate trend analysis and comparisons that would not have been conducted otherwise for lack of human resources. Our case studies illustrate the potential impact on patient safety, quality assurance and process improvement.


 [Link to Report]

Ahn, J., Taieb-Maimon, M., Sopan, A., Plaisant, C., Shneiderman, B. (November 2010)
Temporal Visualization of Social Network Dynamics: Prototypes for Nation of Neighbors
Proc. Of Social Computing, Behavioral-Cultural Modeling and Prediction conference, pp. 309-316, 2011.
HCIL-2010-28

Information visualization is a powerful tool for analyzing dynamic nature of social communities. Using Nation of Neighbors community network as a testbed, we propose five principles of implementing temporal visualizations for social networks and present two research prototypes: NodeXL and TempoVis. Three different states are defined in order to visualize the temporal changes of social networks. We designed the prototypes to show the benefits of the proposed ideas by letting users interactively explore temporal changes of social networks.


 [Link to Report]

Wongsuphasawat, K., Guerra Gomez, J., Plaisant, C., Wang, T., Taieb-Maimon, M., Shneiderman, B. (September 2010)
LifeFlow: Visualizing an Overview of Event Sequences
In Proceedings of the 2011 annual conference on Human factors in computing systems (CHI '11). ACM, New York, NY, USA, 1747-1756. DOI=10.1145/1978942.1979196
HCIL-2010-22

Event sequence analysis is an important task in many domains: medical researchers study the patterns of transfers within the hospital for quality control; transportation experts study accident response logs to identify best practices. In most cases they deal with more than thousands of records. While previous research has focused on searching and browsing, overview tasks are often overlooked. We introduce a novel interactive visual overview of event sequences called LifeFlow. LifeFlow scales to any number of records, summarizes all possible sequences, and highlights the temporal spacing of the events within sequences. We conducted two case studies with healthcare and transportation domain experts to illustrate the usefulness of LifeFlow. We also conducted a user study with ten participants which confirmed that after 15 minutes of training novice users were able to rapidly answer questions about the prevalence and temporal characteristics of sequences, find anomalies, and gain significant insight from the data.


 [Link to Report]

Rind, A., Wang, T., Aigner, W., Miksch, S., Wongsuphasawat, K., Plaisant, C., Shneiderman, B. (September 2010)
Interactive Information Visualization for Exploring and Querying Electronic Health Records: A Systematic Review
Published in Foundations and Trends in Human-Computer Interaction, Vol. 5, No. 3 (2013) 207-298.
HCIL-2010-19

Physicians are confronted with increasingly complex patient histories from which they must make life-critical treatment decisions. At the same time, clinical researchers are eager to study the growing databases of patient histories to detect unknown patterns, ensure quality control, and discover surprising outcomes. Designers of Electronic Health Record systems (EHRs) have great potential to apply innovative visual methods to support clinical decision-making and research. This work surveys the state-of-the-art of information visualization systems for exploring and querying EHRs, as described in the scientific literature. We examine how systems differ in their features and highlight how these differences are related to their design and the medical scenarios they tackle. The systems are compared on a set of criteria: (1) data types covered, (2) multivariate analysis support, (3) number of patient records used (one or multiple), and (4) user intents addressed. Based on our survey and evidence gained from evaluation studies, we believe that effective information visualization can facilitate analysis of EHRs for patient treatment and clinical research. Thus, we encourage the information visualization community to study the application of their systems in health care. Our survey is written for both scientific researchers and designers of future user interfaces for EHRs. We hope it will help them understand this vital domain and appreciate the features and virtues of existing systems so they can create still more advanced systems. We identify potential future research topics in interactive support for data abstraction, in systems for intermittent users such as patients, and in more detailed evaluations.


 [Link to Report]

Guerra Gomez, J., Wongsuphasawat, K., Wang, T., Pack, M., Plaisant, C. (August 2010)
Analyzing Incident Management Event Sequences with Interactive Visualization
In Proceedings of the Transportation Research Board 90th annual meeting, The National Academies, Washington, DC (2011)
HCIL-2010-17

While traditional traffic safety and incident analysis has mostly focused on incident attributes data, such as the road location or the type of vehicle involved in the incident, there are other aspects in incident response that are temporal in nature and are more difficult to analyze. We describe how we used a visual analytics tool called LifeFlow to analyze incident response data. LifeFlow provides user-controlled overviews of event sequences (e.g. notification, arrival, clearance etc). It allows analysts to interactively explore temporal patterns, find anomalies in sequences and compare management practices. This type of analysis can potentially lead to process improvements and save human lives. In our case study we used NCHRP traffic incident data with more than 200,000 incidents reported by 8 different agencies in a period of about 28 months. Our experience suggests that even non expert transportation analysts can spot many anomalies in the data using the LifeFlow overviews, and are able to rapidly ask many questions and find differences between agencies.


 [Link to Report]

Wang, T., Wongsuphasawat, K., Plaisant, C., Shneiderman, B. (June 2010)
Visual Information Seeking in Multiple Electronic Health Records: Design Recommendations and A Process Model
Published in Proceedings of the 1st ACM International Informatics Symposium (IHI '10) (2010) 46-55.
HCIL-2010-12

In the advent of electronic health record (EHR) systems, physicians and clinical researchers enjoy the ease of storage, retrieval, persistence, and sharing of patient data. However, the way physicians interact with EHRs has not changed much. More specifically, task support for temporally analyzing large number of EHRs has been lacking. A number of information visualization techniques have been proposed to alleviate this problem. Unfortunately, due to their limited application to a single case study, the results are often difficult to generalize across medical scenarios. In this paper we present the usage data of and user comments on our information visualization tool Lifelines2 through eight different medical case studies. We generalize our experience into an information- seeking process model for multiple EHRs. Base on our analysis, we make recommendations to future information visualization designers for EHRs on common design requirements and future research directions.


 [Link to Report]

Kang, H., Kang, H., Plaisant, C., Plaisant, C., Elsayed, T., Elsayed, T., Oard, D., Oard, D. (December 2009)
Making Sense of Archived E-mail: Exploring the Enron Collection with NetLens
Published in Journal of the American Society for Information Science and Technology, 61 , 4 (2010) 723-744.
HCIL-2009-37

Informal communications media pose new challenges for information-systems design, but the nature of informal interaction offers new opportunities as well. This paper describes NetLens-E-mail, a system designed to support exploration of the content-actor network in large e-mail collections. Unique features of NetLens-E-mail include close coupling of orientation, specification, restriction, and expansion, and introduction and incorporation of a novel capability for iterative projection between content and actor networks within the same collection. Scenarios are presented to illustrate the intended employment of NetLens-E-mail, and design walkthroughs with two domain experts provide an initial basis for assessment of the suitability of the design by scholars and analysts.


 [Link to Report]

Wang, T., Wongsuphasawat, K., Plaisant, C., Shneiderman, B. (June 2010)
Exploratory Search Over Temporal Event Sequences: Novel Requirements, Operations, and a Process Model
in Proc. Of Third Workshop on Human-Computer Interaction and Information Retrieval (HCIR 2009).
HCIL-2009-35

Developing a detailed requirement analysis facilitates the building of interactive visualization systems that support exploratory analysis of multiple temporal event sequences. We discuss our experiences with collaborators in several domains on how they have used our systems and present a process model for exploratory search as the generalization of our experiences. This process model is intended as an outline of high-level analysis activities, and we hope can be a useful model for future and on-going exploratory search tools.


 [Link to Report]

Freire, M., Plaisant, C., Shneiderman, B., Golbeck, J. (September 2009)
ManyNets: An Interface for Multiple Network Analysis and Visualization
In Proceedings of the 28th international conference on Human factors in computing systems (CHI '10). ACM, New York (2010) 213-222
HCIL-2009-30

Traditional network analysis tools support analysts in studying a single network. ManyNets offers these analysts a powerful new approach that enables them to work on multiple networks simultaneously. Several thousand networks can be presented as rows in a tabular visualization, and then inspected, sorted and filtered according to their attributes. The networks to be displayed can be obtained by subdivision of larger networks. Examples of meaningful subdivisions used by analysts include ego networks, community extraction, and time-based slices. Cell visualizations and interactive column overviews allow analysts to assess the distribution of attributes within particular sets of networks. Details, such as traditional node-link diagrams, are available on demand. We describe a case study analyzing a social network geared towards film recommendations by means of decomposition. A small usability study provides feedback on the use of the interface on a set of tasks issued from the case study.


 [Link to Report]

Wongsuphasawat, K., Plaisant, C., Taieb-Maimon, M., Shneiderman, B. (October 2009)
Querying Event Sequences by Exact Match or Similarity Search: Design and Empirical Evaluation
Interacting with Computers, 24, 2 (2012) 55-68
HCIL-2009-20

Specifying event sequence queries is challenging even for skilled computer professionals familiar with SQL. Most graphical user interfaces for database search use a exact search approach, which is often effective, but applies an exact match criteria. We describe a new similarity-based search interface, in which users specify a query by simply placing events on a blank timeline and retrieve a similarity-ranked list of results. Behind this user interface is a new similarity measure for event sequences which the users can customize by four decision criteria, enabling them to adjust the impact of missing, extra, or swapped events or the impact of time shifts. We describe an example of use with Electronic Health Records based on our ongoing collaboration with hospital physicians. Then we report on a controlled experiment with 18 participants that compared exact search and similarity-based search features. We report on the advantages and disadvantages of each approach and conclude with recommendations for the design of a hybrid approach combining both interfaces.


 [Link to Report]

Vuillemot, R., Clement, T., Plaisant, C., Kumar, A. (April 2009)
What’s Being Said Near "Martha"? Exploring Name Entities in Literary Text Collections
Vuillemot, R.; Clement, T.; Plaisant, C.; Kumar, A.; , "What's being said near "Martha"? Exploring name entities in literary text collections," IEEE Symposium on Visual Analytics Science and Technology, VAST 2009 (2009) 107-114.
doi: 10.1109/VAST.2009.5333248
HCIL-2009-12

A common task in literary analysis is to study characters in a novel or collection. When dealing with large documents or collections automatic entity extraction, text analysis and effective user interfaces might facilitate the exploration of the topics discussed or the vocabulary used in the neighborhood of the characters. Using our interface, called POSvis, the scholar uses word clouds and self-organizing graphs to review the vocabulary in the vicinity of one or more entities, to filter by part of speech, and to explore the network of other characters in that vicinity. Visualizations show word usages within an analysis window (i.e. a book chapter), which can be compared with a reference window (i.e. the whole book). We describe the interface and report on an early case study with a humanities scholar.


 [Link to Report]

Costello, L., Grinstein, G., Plaisant, C., Scholtz, J. (April 2009)
Advancing User-Centered Evaluation of Visual Analytic Environments through Contests
Information Visualization, 8 (2009) 230-238
HCIL-2009-10

In this paper the authors describe the Visual Analytics Science and Technology (VAST) Symposium contests run in 2006 and 2007 and the VAST 2008 and 2009 challenges. These contests were designed to provide researchers with a better understanding of the tasks and data that face potential end users. Access to these end users is limited due to time constraints and the classified nature of the tasks and data. In that respect, the contests serve as an intermediary, with the metrics and feedback serving as measures of utility to the end users. The authors summarize the lessons learned and the future directions for VAST Challenges.


 [Link to Report]

Wang, T., Plaisant, C., Shneiderman, B., Spring, N., Roseman, D., Marchand, G., Mukherjee, V., Smith, M. (April 2009)
Temporal Summaries: Supporting Temporal Categorical Searching, Aggregation and Comparison
Published in IEEE Transactions on Visualization and Computer Graphics (2009) 1049-1056
HCIL-2009-09

When analyzing thousands of event histories, analysts often want to see the events as an aggregate to detect insights and generate new hypotheses about the data. An analysis tool must emphasize both the prevalence and the temporal ordering of these events. Additionally, the analysis tool must also support flexible comparisons to allow analysts to gather visual evidence. In a previsous work, we introduced align, rank, and filter (ARF) to accentuate temporal ordering. In this paper, we present temporal summaries, an interactive visualization technique that highlights the prevalence of event occurrences. Temporal summaries dynamically aggregate events in multiple granularities (year, month, week, day, hour, etc.) for the purpose of spotting trends over time and comparing several groups of records. They provide affordances for analysts to perform temporal range filters. We demonstrate the applicability of this approach in two extensive case studies with analysts who applied temporal summaries to search, filter, and look for patterns in electronic health records and academic records.


 [Link to Report]

Grinstein, G., Plaisant, C., Laskowski, S., O'Connell, T., Scholtz, J., Whiting, M. (November 2008)
VAST 2008 Challenge: Introducing mini-challenges
VAST 2008 Challenge: Introducing mini-challenges, VAST '08. IEEE Symposium on Visual Analytics Science and Technology (2008)195-196
HCIL-2008-34

Visual analytics experts realize that one effective way to push the field forward and to develop metrics for measuring the performance of various visual analytics components is to hold an annual competition. The VAST 2008 Challenge is the third year that such a competition was held in conjunction with the IEEE Visual Analytics Science and Technology (VAST) symposium. The authors restructured the contest format used in 2006 and 2007 to reduce the barriers to participation and offered four minichallenges and a Grand Challenge. Mini Challenge participants were to use visual analytic tools to explore one of four heterogeneous data collections to analyze specific activities of a fictitious, controversial movement. Questions asked in the Grand Challenge required the participants to synthesize data from all four data sets. In this paper we give a brief overview of the data sets, the tasks, the participation, the judging, and the results.


 [Link to Report]

Clement, T., Plaisant, C., Vuillemot, R. (November 2008)
The Story of One: Humanity scholarship with visualization and text analysis
in Proc. Of the Digital Humanities Conference (DH 2009)
HCIL-2008-33

Most critiques of The Making of Americas (Paris 1925) by Gertrude Stein contend that the text deconstructs the role narrative plays in determining identity by using indeterminacy to challenge readerly subjectivity. The current perception of Making as a postmodern text relies on the notion that there is a tension created by frustrated expectations that result from the text’s progressive disbandment of story and plot as the narrative unweaves into seemingly chaotic, meaningless rounds of repetitive words and phrases. Yet, a new perspective that is facilitated by digital tools and based on the highly structured nature of the text suggests that these instabilities can be resolved by the same seemingly nonsensical, non-narrative structures. Seeing the manner in which the structure of the text makes meaning in conversation with narrative alleviates perceived instabilities in the discourse. The discourse about identity formation is engaged—not dissolved in indeterminacy—to the extent that the reader can read the composition.


 [Link to Report]

Jong, C., Rajkumar, P., Siddiquie, B., Clement, T., Plaisant, C., Shneiderman, B. (November 2008)
Interactive Exploration of Versions across Multiple Documents
to appear in Proc. of the Digital Humanities Conference (DH 2009)
HCIL-2008-32

The need to compare two or more documents arises in a variety of situations. Some instances include detection of plagiarism in academic settings and comparing versions of computer programs. Extensive research has been performed on comparing documents based on their content (Si et al., 1997; Brin et al., 1995) and there also exist several tools such as windiff to visually compare a pair of documents. However, little work has been done on providing an effective visual interface to facilitate the comparison of more than two documents simultaneously. Versioning Machine (Schreibman et al., 2003) is a web-based interface that provides the facility to view multiple versions of a document, along with the changes across versions. Motivated by Versioning machine (VM), we build a tool MultiVersioner that facilitates viewing multiple versions of multiple documents at once, and provides the user with a rich set of information regarding their comparison. The primary user during the development of MultiVersioner was Tanya Clement, a doctoral candidate in English at the University of Maryland, who researches the works of experimental poets.


 [Link to Report]

Plaisant, C., Lam, S., Shneiderman, B., Smith, M., Roseman, D., Marchand, G., Gillam, M., Feied, C., Handler, J., Rappaport, H. (May 2008)
Searching Electronic Health Records for Temporal Patterns in Patient Histories: A Case Study with Microsoft Amalga
AMIA Annual Symposium Proceedings (2008) 601-605.
HCIL-2008-13

As electronic health records (EHR) become more widespread, they enable clinicians and researchers to pose complex queries that can benefit immediate patient care and deepen understanding of medical treatment and outcomes. However, current query tools make complex temporal queries difficult to pose, and physicians have to rely on computer professionals to specify the queries for them. This paper describes our efforts to develop a novel query tool implemented in a large operational system at the Washington Hospital Center (Microsoft Amalga, formerly known as Azyxxi). We describe our design of the interface to specify temporal patterns and the visual presentation of results, then summarize the feedback gathered during early testing with physicians. The use case described in the paper focuses on adverse reactions following radiology studies using contrast.


 [Link to Report]

Plaisant, C., Grinstein, G., Scholtz, J., Whiting, M., O'Connell, T., Laskowski, S., Chien, L., Tat, A., Wright, W., Gorg, C., Liu, Z., Parekh, N., Singhal, K., Stasko, J. (January 2008)
Evaluating Visual Analytics: The 2007 Visual Analytics Science and Technology Symposium Contest
IEEE Computer Graphics and Applications, 28, 2, 12-21 (2008)
HCIL-2008-04

The second Visual Analytics Science and Technology (VAST) contest’s data consisted of a heterogeneous synthetic collection of news articles with additional supporting files and contained a scenario with embedded threats that provided ground truth. Using visual analytic tools, participants sought evidence of illegal and terrorist activities. We describe the contest and the evaluation methodology. We report results and lessons learned.


 [Link to Report]

Wang, T., Plaisant, C., Quinn, A., Stanchak, R., Shneiderman, B., Murphy, S. (January 2008)
Aligning Temporal Data by Sentinel Events: Discovering Patterns in Electronic Health Records
Proc. of ACM Conference on Human Factors in Computing Systems (2008) 457-466
HCIL-2007-28

Electronic Health Records (EHRs) and other temporal databases contain hidden patterns that reveal important cause-and-effect phenomena. Finding these patterns is a challenge when using traditional query languages and tabular displays. We present an interactive visual tool that complements query formulation by providing operations to align, rank and filter the results, and to visualize estimates of the intervals of validity of the data. Display of patient histories aligned on sentinel events (such as a first heart attack) enables users to spot precursor, co-occurring, and aftereffect events. A controlled study demonstrates the benefits of providing alignment (with a 61% speed improvement for complex tasks). A qualitative study and interviews with medical professionals demonstrates that the interface can be learned quickly and seems to address their needs.


 [Link to Report]

Gregory, M., Don, A., Zheleva, E., Tarkan, S., Plaisant, C., Shneiderman, B. (October 2007)
Shape Search in Temporal Data to Facilitate Knowledge Discovery: A User Interface to find Spikes, Sinks and Slopes
HCIL-2007-16

The ability to find interesting patterns in sequential datasets is important in both data analysis and knowledge discovery. Shapes, such as spikes, valleys, and increasing lines, created when graphing sequential data points are familiar to analyst as a way of identifying trends and anomalous behaviors. This work presents a set of common shapes that can be used by visualization designers to assist users in discovering patterns in data that may be interesting. Each shape has a set of characteristics that can be used to rank their “interestingness.” A way of identifying each shape and the characteristics used to rank them are presented in this paper. To explore the usefulness of shape identification and characteristic ranking a case study was done. The case study incorporated the methods of shape identification and ranking presented in this paper into the FeatureLens tool, an interface to explore and visualize features in collections of text documents.


 [Link to Report]

Bederson, B., Clamage, A., Plaisant, C. (January 2008)
Enhancing In-Car Navigation Systems with Personal Experience
Proceedings of the Transportation Research Board 87th annual meeting, The National Academies, Washington, DC (2008) 1-11[ Published Version] Also Journal of the Transportation Research Board of the National Academies, 2064 (2008) 33-42
HCIL-2007-11

Computers are extremely powerful for data processing, but less adept at handling problems that involve subjective reasoning. People, on the other hand, are very good at these kinds of problems. We present a framework for adding subjective human experience to in-car navigation systems. People often rely on their own experience when planning trips, choosing the route that seemed fastest in the past, the one that was the prettiest, or the one recommended by a friend. This led us to develop a set of methods to help people record their personal driving history, add rich annotations, and share their data with friends and family, or even the broader community. Users can then learn from their own data, or harness the multiplicity of individual experiences to enjoy new routes. This approach can be used in conjunction with traditional in-car navigation systems.


 [Link to Report]

Don, A., Zheleva, E., Gregory, M., Tarkan, S., Auvil, L., Clement, T., Shneiderman, B., Plaisant, C. (May 2007)
Discovering interesting usage patterns in text collections: integrating text mining with visualization
Proceedings of the sixteenth ACM conference on Conference on information and knowledge management, 2007, p. 213 - 222.
HCIL-2007-08

This paper addresses the problem of making text mining results more comprehensible to humanities scholars, journalists, intelligence analysts, and other researchers, in order to support the analysis of text collections. Our system, FeatureLens[1], visualizes a text collection at different levels of granularity and enables users to discover interesting text patterns. Text patterns are defined as frequent itemsets of n-grams, and they capture the repetition of exact or similar expressions in the collection. Users can find meaningful co-occurrences of text patterns by visualizing them within and across documents in the collection. This also permits users to identify the temporal evolution of usage such as increasing, decreasing or sudden appearance of text patterns. Initial studies suggest that the proposed visualization helped a literary scholar and 8 advanced-degree users create new hypotheses and make interesting insights about 2 analyzed text collections.


 [Link to Report]

Buono, P., Plaisant, C., Simeone, A., Aris, A., Shneiderman, B., Shmueli, G., Jank, W. (April 2007)
Similarity-Based Forecasting with Simultaneous Previews: A River Plot Interface for Time Series Forecasting
Similarity-Based Forecasting with Simultaneous Previews: A River Plot Interface for Time Series Forecasting,Proc. of the 11th International Conference Information Visualization (IV '07), 2007, 191-196
HCIL-2007-05

Time-series forecasting has a large number of applications. Users with a partial time series for auctions, new stock offerings, or industrial processes desire estimates of the future behavior. We present a data driven forecasting method and interface called Similarity-Based Forecasting (SBF). A pattern matching search in a dataset of historical time series produces a subset of curves similar to the partial time series. The forecast is displayed graphically as a river plot showing statistical information about the SBF subset. A forecasting preview interface allows users to interactively explore alternative pattern matching parameters and see multiple forecasts simultaneously. User testing with 8 users demonstrated advantages and led to improvements.


 [Link to Report]

Zhao, H., Shneiderman, B., Plaisant, C., Lazar, J. (August 2006)
Data sonification for users with visual impairments: A case study with geo-referenced data
ACM Transactions on Computer Human Interaction 15, 1 (May 2008), Article 4.
HCIL-2006-22

We describe an Action-by-Design-Component (ADC) framework to guide auditory interface designers for exploratory data analysis. The framework characterizes data interaction in the auditory mode as a set of Auditory Information Seeking Actions (AISAs). Contrasting AISAs with actions in visualizations, the framework also discusses design considerations for a set of Design Components to support AISAs. Applying the framework to geo-referenced data, we systematically explored and evaluated its design space. A data exploration tool, iSonic, was built for blind users. In depth case studies with 7 blind users, with over 42 hours of data collection, showed that iSonic enabled them to find facts and discover trends of geo-referenced data, even in unfamiliar geographical contexts, without special devices. The results also showed that blind users dramatically benefited from the rich set of task-oriented actions (AISAs) and the use of multiple highly coordinated data views provided by the ADC framework. Some widely used techniques in visualization, with appropriate adaptation, also work in the auditory mode. The application of the framework to scatterplots shows that the framework can be generalized and lead to the design of a unified auditory workspace for general exploratory data analysis. Readers can view a supplementary video demonstration of iSonic by visiting www.cs.umd.edu/hcil/iSonic/.


 [Link to Report]

Lee, B., Plaisant, C., Parr, C., Fekete, J., Henry, N. (May 2006)
Task Taxonomy for Graph Visualization
Proceedings of BELIV '06, pp.81-85.
HCIL-2006-13

Our goal is to define a list of tasks for graph visualization that has enough detail and specificity to be useful to designers who want to improve their system and to evaluators who want to compare graph visualization systems. In this paper, we suggest a list of tasks we believe are commonly encountered while analyzing graph data. We define graph specific objects and demonstrate how all complex tasks could be seen as a series of low-level tasks performed on those objects. We believe that our taxonomy, associated with benchmark datasets and specific tasks, would help evaluators generalize results collected through a series of controlled experiments.


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Shneiderman, B., Plaisant, C. (May 2006)
Strategies for Evaluating Information Visualization Tools: Multi-dimensional In-depth Long-term Case Studies
Proceedings of BELIV '06, pp.38-43.
HCIL-2006-12

After an historical review of evaluation methods, we describe an emerging research method called Multi-dimensional In-depth Long-term Case studies (MILCs) which seems well adapted to study the creative activities that users of information visualization systems engage in. We propose that the efficacy of tools can be assessed by documenting 1) usage (observations, interviews, surveys, logging etc.) and 2) expert users’ success in achieving their professional goals. We summarize lessons from related ethnography methods used in HCI and provide guidelines for conducting MILCs for information visualization. We suggest ways to refine the methods for MILCs in modest sized projects and then envision ambitious projects with 3-10 researchers working over 1-3 years to understand individual and organizational use of information visualization by domain experts working at the frontiers of knowledge in their fields.


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Kang, H., Plaisant, C., Lee, B., Bederson, B. (May 2006)
NetLens: Iterative Exploration of Content-Actor Network Data
Proceedings of IEEE Symposium on Visual Analytics Science and Technology (VAST 2006), 91 - 98.
HCIL-2006-10

Networks have remained a challenge for information retrieval and visualization because of the rich set of tasks that users want to accomplish. This paper offers an abstract Content-Actor network data model, a classification of tasks, and a tool to support them. The NetLens interface was designed around the abstract Content-Actor network data model to allow users to pose a series of elementary queries and iteratively refine visual overviews and sorted lists. This enables the support of complex queries that are traditionally hard to specify. NetLens is general and scalable in that it applies to any dataset that can be represented with our abstract data model. This paper describes NetLens applying a subset of the ACM Digital Library consisting of about 4,000 papers from the CHI conference written by about 6,000 authors. In addition, we are now working on a collection of half a million emails, and a legal cases dataset.


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Lee, B., Parr, C., Plaisant, C., Bederson, B., Veksler, V., Gray, W., Kotfila, C. (February 2006)
TreePlus: Interactive Exploration of Networks with Enhanced Tree Layouts
IEEE Transactions Transactions on Visualization and Computer Graphics, 12, 6, 1414-1426.
HCIL-2006-04

Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food webs, ontologies, and social networks difficult to understand and interact with. We propose a new interactive Visual Analytics component called TreePlus that is based on a tree-style layout. TreePlus reveals the missing graph structure with visualization and interaction while maintaining good readability. To support exploration of the local structure of the graph and gathering of information from the extensive reading of labels, we use a guiding metaphor of "Plant a seed and watch it grow." It allows users to start with a node and expand the graph as needed, which complements the classic overview techniques than can be effective at - but often limited to - revealing clusters. We describe our design goals, describe the interface, and report on a controlled user study with 28 participants comparing TreePlus with a traditional graph interface for six tasks. In general, the advantage of TreePlus over the traditional interface increased as the density of the displayed data increased. Participants also reported higher levels of confidence in their answers with TreePlus and most of them preferred TreePlus.


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Plaisant, C., Rose, J., Yu, B., Auvil, L., Kirschenbaum, M., Smith, M., Clement, T., Lord, G. (January 2006)
Exploring Erotics in Emily Dickinson's Correspondence with Text Mining and Visual Interfaces
Proceedings of the 6th ACM/IEEE Joint Conference on Digital Libraries, JCDL 06, 141-150 (nominated for Best Paper award)
HCIL-2006-01

This paper describes a system to support humanities scholars in their interpretation of literary work. It presents a user interface and web architecture that integrates text mining, a graphical user interface and visualization, while attempting to remain easy to use by non specialists. Users can interactively read and rate documents found in a digital libraries collection, prepare training sets, review results of classification algorithms and explore possible indicators and explanations. Initial evaluation steps suggest that there is a rationale for “provocational” text mining in literary interpretation.


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Plaisant, C., Shneiderman, B., Baker, H., Duarte, N., Haririnia, A., Klinesmith, D., Lee, H., Velikovich, L., Wanga, A., Westhoff, M. (November 2005)
Personal Role Management: Overview and a Design Study of Email for University Students
To appear in: Kaptelinin, V., Czerwinski, M. (Eds) Integrated Digital Work Environments: Beyond the Desktop, MIT Press, (This is an expansion on HCIL-2003-30), (2007) 143-170.
HCIL-2005-30

Evidence is accumulating about the difficulties that users have in managing their work using contemporary graphical user interfaces. Current designs offer a hierarchy of folders containing documents and taskbar operations to launch/exit applications. We propose a Personal Role Management strategy that emphasizes management of the multiple roles users have in their professional and personal lives. Each role involves coordination with groups of people and accomplishment of tasks within a schedule. We define Personal Role Management and summarize our earlier work that led to this strategy. This current project focused on understanding how Personal Role Management might improve email for college students. College students often assume distinct and predictable roles. Their student role is structured by the rhythm and interactions of classes, projects and exams. In both their family role and their work role for local companies, they deal with separate groups of people. We describe scenarios of use of a role-based email system, an interface mockup and user reactions. This research suggests that using those roles as a driving component for designing an email interface might address problems identified in our surveys and interviews of college students.


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Zhao, H., Plaisant, C., Shneiderman, B. (October 2005)
A Framework for Auditory Data Exploration and Evaluation with Geo-referenced Data Sonification
This report was updated and improved by TR HCIL-2006-22
HCIL-2005-28

We first describe an Action-by-Design-Component (ADC) framework to guide auditory interface designs for exploratory data analysis. Applying the framework to the interactive sonification of geo-referenced data, we systematically explored and evaluated its design space. A data exploration tool, iSonic, was implemented for users with vision impairment. In depth case studies with 7 blind users showed that iSonic enabled them to find facts and discover data trends of geo-referenced data, even in unfamiliar geographical contexts. Analysis of user task behaviors and usage patterns confirmed that the framework has captured auditory information seeking actions and components that were naturally adopted by subjects to accomplish geo-referenced data exploration tasks. The results provide evidence for us to extend the framework, and guidance for designers of unified auditory workspaces for general exploratory data analysis.


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Lee, B., Parr, C., Plaisant, C., Bederson, B. (Sept 2005)
Visualizing Graphs as Trees: Plant a Seed and Watch it Grow
Proceedings of Graph Drawing 2005, pp. 516-518.
HCIL-2005-23

TreePlus is a graph browsing technique based on a tree-style layout. It shows the missing graph structure using interaction techniques and enables users to start with a specific node and incrementally explore the local structure of graphs.? We believe that it supports particularly well tasks that require rapid reading of labels.


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Zhao, H., Plaisant, C. (May 2005)
InterSon: Interactive Sonification for Geo-referenced Data Exploration for the Vision Impaired
HCIL-2005-13, CS-TR-4751, UMIACS-TR-2005-54

Abstract. InterSon is an interactive sonification tool that allows vision im-paired users to explore complex geo-referenced statistical data for fact finding, problem solving and decision making. Examples include maps of population density, crime rates or housing prices. The integrated use of sounds and speech allows users to hear the overall distribution of values on maps and to explore the map to get more details. Users can use the standard computer keyboard, or take advantage of special devices such as a touchpad when they are available. Synchronized auditory and visual displays allow the use of residual vision and facilitate collaboration with sighted colleagues. The prototype was developed at the University of XXXX and is being evaluated with vision impaired users at the University of XXXX.


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Eaton, C., Plaisant, C., Drizd, T. (March 2005)
Visualizing Missing Data: Classification and Empirical Study
Proc. of INTERACT 2005, Springer, Berlin (861-872). Springer Link: http://dx.doi.org/10.1007/11555261_68
HCIL-2005-05, CS-TR-4709, UMIACS-TR-2005-17

Most visualization tools fail to provide support for missing data. We identify sources of missing, and categorize data visualization techniques based on the impact missing data have on the display: region dependent, attribute dependent, and neighbor dependent. We then report on a user study with 30 participants that compared three design variants. A between-subject graph interpretation study provides strong evidence for the need of indicating the presence of missing information, and some direction for addressing the problem.


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Plaisant, C., Shneiderman, B. (February 2005)
Show Me! Guidelines for Producing Recorded Demonstrations
Proceedings of 2005 IEEE Symposium on Visual Languages and Human-Centric Computing, (VL/HCC'05), 171 - 178.
HCIL-2005-02, CS-TR-4712, UMIACS-TR-2005-20, ISR-TR-2005-72

Although recorded demonstrations (screen capture animations with narration) have become a popular form of instruction for user interfaces, little work has been done to describe guidelines for their design. Based on our experience in several projects, we offer a starting set of guidelines for the design of recorded demonstrations. Technical guidelines encourage users to keep file sizes small, strive for universal usability, and ensure user control etc. and provide tips to achieve those goals. Content guidelines include: create short demonstrations that focus on tasks, highlight each step with auditory and visual cues, synchronize narration and animation carefully, and create demonstrations with a clear beginning, middle, and end.


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Aris, A., Shneiderman, B., Plaisant, C., Shmueli, G., Jank, W. (February 2005)
Representing Unevenly-Spaced Time Series Data for Visualization and Interactive Exploration
Proc. of INTERACT 2005, Springer, Berlin (835-846). Springer Link http://dx.doi.org/10.1007/11555261_66
HCIL-2005-01, CS-TR-4713, UMIACS-TR-2005-21, ISR-TR-2005-73

Visualizing time series data is useful to support discovery of relations and patterns in financial, genomic, medical and other applications. In most time series, measurements are equally spaced over time. This paper discusses the challenges for unevenly-spaced time series data and presents four methods to represent them: sampled events, aggregated sampled events, event index and interleaved event index. We developed these methods while studying eBay auction data with TimeSearcher. We describe the advantages, disadvantages, choices for algorithms and parameters, and compare the different methods. Since each method has its advantages, this paper provides guidance for choosing the right combination of methods, algorithms, and parameters to solve a given problem for unevenly-spaced time series. Interaction issues such as screen resolution, response time for dynamic queries, and meaning of the visual display are governed by these decisions.


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Plaisant, C. (January 2005)
Information Visualization and the Challenge of Universal Access
In Exploring Geovisualization (Eds, J. Dykes, A. MacEachren and M.J. Kraak), Oxford: Elsevier (2005) 53-82.
HCIL-2004-36, CS-TR-4717, UMIACS-TR-2005-25

Information Visualization aims to provide compact graphical presentations and user interfaces for interactively manipulating large numbers of items. We present a simple “data by tasks taxonomy” then discuss the challenges of providing universal usability, with example applications using geo-referenced data. Information Visualization has been shown to be a powerful visual thinking or decision tool but it is becoming important for services to reach and empower every citizen. Technological advances are needed to deal with user diversity (age, language, disabilities, etc.) but also with the variety of technology used (screen size, network speed, etc.) and the gaps in user's knowledge (general knowledge, knowledge of the application domain, of the interface syntax or semantic). We present examples that illustrate how those challenges can be addressed.


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Zhao, H., Plaisant, C., Shneiderman, B. (January 2005)
"I Hear the Pattern" - Interactive Sonification of Geographical Data Patterns
ACM SIGCHI 2005 Extended Abstracts on Human Factors in Computing Systems
HCIL-2004-35, CS-TR-4718, UMIACS-TR-2005-26, ISR-TR-2005-64

In this paper we describe our investigation of using interactive sonification (non-speech sound) to present the geographical distribution pattern of statistical data to vision impaired users. We first discuss the design space in the dimensions of interaction actions, data representation forms, input devices, navigation structures, and sound feedback encoding. Two interfaces have been designed according to the design space, one using a keyboard and another using a smooth surface touch tablet. A study with three blind users shows that they are able to perceive patterns of 5-category values on both familiar and unknown maps, and learn new map geography, in both interfaces.


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Plaisant, C., Fekete, J., Grinstein, G.
Promoting Insight Based Evaluation of Visualizations: From Contest to Benchmark Repository
Promoting Insight Based Evaluation of Visualizations: From Contest to Benchmark Repository, ACM Transactions on Visualization and Computer Graphics , 14, 1 (2008) 120-134
HCIL-2004-30

Information Visualization (InfoVis) is now an accepted and growing field with numerous visualization components used in many applications. However, questions about the potential uses and maturity of novel visualizations remain. Usability studies and controlled experiments are helpful but generalization is difficult. We believe that the systematic development of benchmarks will facilitate the comparison of techniques and help identify their strengths under different conditions. A benchmark typically consists of a dataset, a list of tasks, and a list of non-trivial discoveries. We were each involved in the organization of three information visualization contests for the 2003, 2004 and 2005 IEEE Information Visualization Symposia. Our goal is to encourage the development of benchmarks, push the forefront of the InfoVis field by making difficult problems available, create a forum for the discussion of evaluation and provide an interesting event at the InfoVis conference. The materials produced by the contests are archived in the Information Visualization Benchmark Repository. We review the state of the art and challenges of evaluation in InfoVis, describe the three contests, summarize their results, discuss outcomes and lessons learned, and conjecture the future of visualization contests.


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Marchionini, G., Haas, S., Plaisant, C., Shneiderman, B., Hert, C. (November 2004)
Project Highlight: Toward a Statistical Knowledge Network
Proc. National Conference on Digital Government Research, (2004), 93-94 http://www.dgrc.org/dgo2004
HCIL-2004-28, CS-TR-4637, UMIACS-TR-2004-79, ISR-TR-2005-60


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Buono, P., Aris, A., Plaisant, C., Khella, A., Shneiderman, B. (October 2004)
Interactive Pattern Search in Time Series
Proceedings of Conference on Visualization and Data Analysis, VDA 2005, SPIE, Washington DC (2005) 175-186.
HCIL-2004-25, CS-TR-4634, UMIACS-TR-2004-76, ISR-TR-2005-57

The need for pattern discovery in long time series data led researchers to develop algorithms for similarity search. Most of the literature about time series focuses on algorithms that index time series and bring the data into the main storage, thus providing fast information retrieval on large time series. This paper reviews the state of the art in visualizing time series, and focuses on techniques that enable users to interactively query time series. Then it presents TimeSearcher 2, a tool that enables users to explore multidimensional data using coordinated tables and graphs with overview+detail, filter the time series data to reduce the scope of the search, select an existing pattern to find similar occurrences, and interactively adjust similarity parameters to narrow the result set. This tool is an extension of previous work, TimeSearcher 1, which uses graphical timeboxes to interactively query time series data.


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Zhao, H., Smith, B., Norman, K., Plaisant, C., Shneiderman, B. (May 2004)
Interactive Sonification of Choropleth Maps: Design and Evaluation
IEEE multimedia, Special issue on Interactive Sonification, 12, 2 (2005) 26 -35.
HCIL-2004-23, CS-TR-4651, ISR-TR-2005-56

In this paper, we summarize the Auditory Information Seeking Principle (AISP) (gist, navigate, filter, and details-ondemand). To improve blind access to geo-referenced statistical data, we developed several interactive sonifications, adhering to the above AISP. Two user studies are presented. In the first user study with nine sighted subjects, a preliminary map design is compared with an enhanced table design. The study shows subjects can recognize geographic data distribution patterns on a real map with 51 geographic regions, in both designs. The map-based design was strongly preferred. The study also shows evidence that AISP conforms to people's information seeking strategies. Based on the observations from the first user study, a second user study was conducted with forty-eight sighted subjects comparing four map designs. The effects of using sound to encode vertical geographic positions and two map navigation methods were compared. The result is presented and future work is discussed.


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Plaisant, C. (May 2004)
The Challenge of Information Visualization Evaluation
Proc. of Conf. on Advanced Visual Interfaces AVI'04 (2004), p.109-116.
HCIL-2004-19, CS-TR-4655

As the field of information visualization matures, the tools and ideas described in our research publications are reaching users. The reports of usability studies and controlled experiments are helpful to understand the potential and limitations of our tools, but we need to consider other evaluation approaches that take into account the long exploratory nature of users tasks, the value of potential discoveries or the benefits of overall awareness. We need better metrics and benchmark repositories to compare tools, and we should also seek reports of successful adoption and demonstrated utility.


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Chintalapani, G., Plaisant, C., Shneiderman, B. (April 2004)
Extending the Utility of Treemaps with Flexible Hierarchy
Proc. International Conference on Information Visualization, (2004), 335-344.
HCIL-2004-10, CS-TR-4663, ISR-TR-2005-52

Treemaps is a visualization technique for presenting hierarchical information on two dimensional displays. Prior implementations limit the visualization to pre-defined static hierarchies. Flexible hierarchy, a new capability of Treemap 4.0, enables users to define various hierarchies through dynamically selecting a series of data attributes so that they can discover patterns, clusters and outliers. This paper describes the design and implementation issues of flexible hierarchy. It then reports on a usability study which led to enhancements to the interface.


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Zhao, H., Plaisant, C., Shneiderman, B., Duraiswami, R. (February 2004)
Sonification of Geo-Referenced Data for Auditory Information Seeking: Design Principle and Pilot Study
Proc. International Conference on Auditory Displays (2004), (http://www.icad.org)
HCIL-2004-04, CS-TR-4669, ISR-TR-2005-36

We present an Auditory Information Seeking Principle (AISP) (gist, navigate, filter, and details-on-demand) modeled after the visual information seeking mantra [1]. We propose that data sonification designs should conform to this principle. We also present some design challenges imposed by human auditory perception characteristics. To improve blind access to geo-referenced statistical data, we developed two preliminary sonifications adhering to the above AISP, an enhanced table and a spatial choropleth map. Our pilot study shows people can recognize geographic data distribution patterns on a real map with 51 geographic regions, in both designs. The study also shows evidence that AISP conforms to people's information seeking strategies. Future work is discussed, including the improvement of the choropleth map design.


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Eaton, C., Plaisant, C., Drizd, T. (December 2003)
The Challenge of Missing and Uncertain Data
In Visualization 2003 Conference poster abstract compendium, IEEE, (2003) 40-41
HCIL-2003-45, CS-TR-4673

Although clear recognition of missing and uncertain data is essential for accurate data analysis, most visualization techniques do not adequately support these significant data set attributes. After reviewing the sources of missing and uncertain data we propose three categories of visualization techniques based on the impact that missing data has on the display. Finally, we propose a set of general techniques that can be used to handle missing and uncertain data.


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Plaisant, C., Bederson, B., Clamage, A., Hutchinson, H., Druin, A. (October 2003)
Shared Family Calendars: Promoting Symmetry and Accessibility
ACM Transactions on Computer-Human Interaction, 13, 3 (2006) 313 - 346.
HCIL-2003-38, CS-TR-4680

We demonstrate a system facilitating the sharing of calendar information between remotely located family members. Depending on their preference, some users enter information into computerized calendars, while others handwrite on digital paper calendars. All of the information is automatically viewable by everyone in the family.


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Fekete, J., Wang, D., Dang, N., Aris, A., Plaisant, C. (August 2003)
Overlaying Graph Links on Treemaps
In Information Visualization 2003 Symposium Poster Compendium, IEEE, (2003) 82-83
HCIL-2003-32, CS-TR-4686

Every graph can be decomposed into a tree structure plus a set of remaining edges. We describe a visualization technique that displays the tree structure as a Treemap and the remaining edges as curved links overlaid on the Treemap. Link curves are designed to show where the link starts and where it ends without requiring an explicit arrow that would clutter the already dense visualization. This technique is effective for visualizing structures where the underlying tree has some meaning, such as Web sites or XML documents with cross-references. Graphic attributes of the links such as color or thickness can be used to represent attributes of the edges. Users can choose to see all links at once or only the links to and from the node or branch under the cursor.


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Baker, H., Duarte, N., Haririnia, A., Klinesmith, D., Lee, H., Velikovich, L., Wanga, A., Westhoff, M., Plaisant, C. (June 2003)
A Design Study of the Integration of Email and Role Management for University Students
(This TR was revised and expanded into HCIL-2005-30)
HCIL-2003-30, CS-TR-4687

In order to accommodate the increasing diversity of email users, applications have evolved in both functionality and user interface. In this study, we attempt to determine whether email user interfaces can be improved to serve a specific target population: college students. We present our results from college campus surveys that examine email usage patterns and subjective experiences among college students. From our survey feedback and related research, we conclude that email overload and feature intimidation are the greatest hindrances to email communication on campus. To address these problems, we propose employing role management to organize messages calendar and contacts in an email program for students, using school, work and family roles. We describe a prototype and user reactions. Our conclusion is that role management, integrated into email software, may help college students manage their email more effectively.


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Kules, B., Kang, H., Plaisant, C., Rose, A., Shneiderman, B. (April 2003)
Immediate Usability: A Case Study of Public Access Design for a Community Photo Library
Interacting with Computers, 16, 3, December 2004, 1171-1193.
HCIL-2003-22, CS-TR-4481, UMIACS-TR-2003-50, ISR-TR-2005-42

This paper describes a novel instantiation of a digital photo library in a public access system. It demonstrates how designers can utilize characteristics of a target user community (social constraints, trust, and a lack of anonymity) to provide capabilities that would be impractical in other types of public access systems. It also presents a compact set of design principles and guidelines for ensuring the immediate usability of public access information systems. These principles and guidelines were derived from our experience developing PhotoFinder Kiosk, a community photo library. Attendees of a major HCI conference (CHI 2001 Conference on Human Factors in Computing Systems) successfully used the tool to browse and annotate collections of photographs spanning 20 years of HCI-related conferences, producing a richly annotated photo history of the field of human-computer interaction. Observations and log data were used to evaluate the tool and develop the guidelines. They provide specific guidance for practitioners, as well as a useful framework for additional research in public access interfaces.


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Zhao, H., Plaisant, C., Shneiderman, B. (March 2003)
Improving Accessibility and Usability of Geo-referenced Statistical Data
Proc. of the Digital Government Research Conference, 147-150, http://www.dgrc.org/dgo2004
HCIL-2003-11, CS-TR-4467, UMIACS-TR-2003-37, ISR-TR-2005-40

Several technology breakthroughs are needed to achieve the goals of universal accessibility and usability. These goals are especially challenging in the case of geo-referenced statistical data that many U.S. government agencies supply. We present technical and user-interface design challenges in accommodating users with low-end technology (slow network connection and low-end machine) and users who are blind or vision-impaired. Our solutions are presented and future work is discussed.


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Kang, H., Plaisant, C., Shneiderman, B. (March 2003)
New Approaches to Help Users Get Started with Visual Interfaces: Multi-Layered Interfaces and Integrated Initial Guidance
Proc. of the Digital Government Research Conference, 141-146, http://www.dgrc.org/dgo2004
HCIL-2003-10, CS-TR-4466, UMIACS-TR-2003-36, ISR-TR-2005-39

We are investigating new ways to help users learn to use public access interactive tools, in particular for the visual exploration of government statistics. Our work led to a series of interfaces using multi-layered design and a new help method called Integrated Initial Guidance. Multi-layer designs structure an interface so that a simpler interface is available for users to get started and more complex features are accessed as users move through the more advanced layers. Integrated Initial Guidance provides help within the working interface, right at the start of the application. Using the metaphor of “sticky notes” overlaid on top of the functional interface locates the main widgets, demonstrates their manipulation, and explains the resulting actions using preset animation of the interface. Additional sticky notes lead to example tasks, also being executed step by step within the interface itself. Usability testing with 12 participants led to refined designs and guidelines for the design of Integrated Initial Guidance interfaces.


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Kules, B., Shneiderman, B., Plaisant, C. (March 2003)
Data Exploration with Paired Hierarchical Visualizations: Initial Designs of PairTrees
Proc. of the Digital Government Research Conference, 255-260, http://www.dgrc.org/dgo2004
HCIL-2003-09, CS-TR-4465, UMIACS-TR-2003-35, ISR-TR-2005-38

Paired hierarchical visualizations (PairTrees) integrate treemaps, node-link diagrams, choropleth maps and other information visualization techniques to support exploration of hierarchical data sets at multiple levels of abstraction. This paper describes several novel applications of PairTrees in the econometric and health statistics domains, as well as some challenges and trade-offs inherent in the technique.


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Hutchinson, H., Bederson, B., Plaisant, C., Druin, A. (October 2002)
Family Calendar Survey
HCIL-2002-21, CS-TR-4412, UMIACS-TR-2002-92

Beginning in late July 2002, we conducted a survey about people's personal and family calendaring habits. By the end of September, we had over 400 responses, which are summarized below. The survey was conducted to help inform our work in designing new technologies for families, motivated in part by our work on the interLiving project. InterLiving is a 3 year, European Union-funded project where we work with distributed, multi-generational families as design partners to create new technologies (see http://www.cs.umd.edu/hcil/interliving for details). The survey was administered from a web page (https://www.cs.umd.edu/users/hilary/survey/survey.htm), and participants were solicited via a "chain-mail" email approach. We began by sending a request to fill out a survey to our friends, families, and colleagues. We asked that they forward the request on to their friends, family and colleagues as well. While we realize that this was an imperfect approach, we believed that the respondents would be representative of the users we are initially targeting in our research on family calendaring and coordination -- individuals who are already making relatively heavy use of computers at home and/or work. The results seem to validate this assumption. Many of our respondents likely come from the HCI community as the mailing went to our large lab mailing list. We may have some pollution in the data as a result of people in the same household (e.g. husband and wife) both filling out the survey. Despite these issues, the results we got were helpful in eliciting a number of important findings, namely that people rely on multiple calendars, many of which are still paper.


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Hutchinson, H., Bederson, B., Druin, A., Plaisant, C., Mackay, W., Evans, H., Hansen, H., Conversy, S., Beaudouin-Lafon, M., Roussel, N., Lacomme, L., Eiderbäck, B., Lindquist, S., Sundblad, Y., Westerlund, B. (September 2002)
Technology Probes: Inspiring Design for and with Families
ACM Conference on Computer-Human Interaction (CHI 2003), pp. 17-24.
HCIL-2002-16, CS-TR-4407, UMIACS-TR-2002-87

We describe a new methodology for designing technologies for and with families called technology probes. Technology probes are simple, flexible, adaptable technologies introduced into families' homes with three interdisciplinary goals: the social science goal of collecting data about the use of the technology in a real-world setting, the engineering goal of field-testing the technology, and the design goal of inspiring users and designers to think about new technologies. We present the results of designing and deploying two technology probes, the MessageProbe and the VideoProbe, with families in France, Sweden, and the U.S. We conclude with our plans for creating new technologies based on our experiences. Keywords Design Methods, Computer Mediated Communication, Computer Supported Cooperative Work (CSCW), Home, Ethnography, Participatory Design and Cooperative Design, User Studies and Fieldwork


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Shneiderman, B., Kang, H., Kules, B., Plaisant, C., Rose, A., Rucheir, R. (August 2002)
A Photo History of SIGCHI: Evolution of Design from Personal to Public
ACM Interactions, 9, 3 (May 2002), 17-23.
HCIL-2002-14, CS-TR-4397, UMIACS-TR-2002-77, ISR-TR-2005-67

For 20 years I have been photographing personalities and events in the emerging discipline of human-computer interaction. Until now, only a few of these photos were published in newsletters or were shown to visitors who sought them out. Now this photo history is going from a personal record to a public archive. This archive should be interesting for professional members of this community who want to reminisce, as well as for historians and journalists who want to understand what happened. Students and Web surfers may also want to look at the people who created better interfaces and more satisfying user experiences.


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Plaisant, C., Grosjean, J., Bederson, B. (April 2002)
SpaceTree: Supporting Exploration in Large Node Link Tree, Design Evolution and Empirical Evaluation
INFOVIS 2002. IEEE Symposium on Information Visualization, 2002, Page(s): 57 -64, Boston, October 2002.
HCIL-2002-05, CS-TR-4360, UMIACS-TR-2002-40

We present a novel tree browser that builds on the conventional node link tree diagrams. It adds dynamic rescaling of branches of the tree to best fit the available screen space, optimized camera movement, and the use of preview icons summarizing the topology of the branches that cannot be expanded. In addition, it includes integrated search and filter functions. This paper reflects on the evolution of the design and highlights the principles that emerged from it. A controlled experiment showed benefits for navigation to already previously visited nodes and estimation of overall tree topology.


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Fekete, J., Plaisant, C. (January 2002)
Interactive Information Visualization of a Million Items
INFOVIS 2002. IEEE Symposium on Information Visualization, 2002, Page(s): 117 -124, Boston, October 2002.
HCIL-2002-01, CS-TR-4320, UMIACS-TR-2002-2

Existing information visualization techniques are usually limited to the display of a few thousand items. This article describes new interactive techniques capable of handling a million items (effectively visible and manageable on screen). We evaluate the use of hardware-based techniques available with newer graphics cards, as well as new animation techniques and non-standard graphical features such as stereovision and overlap count. These techniques have been applied to two popular information visualizations: treemaps and scatter plot diagrams; but are generic enough to be applied to other representations as well. Keywords I.3.6 Methodology and Techniques; H.5.2 User Interfaces; I.3.3 Picture/Image Generation.


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Kules, B., Kang, H., Plaisant, C., Rose, A., Shneiderman, B. (October 2001)
Immediate Usability: Kiosk Design Principles from the CHI 2001 Photo Library
This paper has been updated and replaced by HCIL-2003-22
HCIL-2001-23, CS-TR-4293, UMIACS-TR-2001-71, ISR-TR-2005-25

This paper describes a novel set of design principles and guidelines for ensuring the immediate usability of public access systems. These principles and guidelines were formulated while developing PhotoFinder Kiosk, a community photo library. Attendees of CHI 2001 successfully used the tool to browse and annotate collections of photographs spanning 20 years of CHI and related conferences, producing a richly annotated photo history of the field of human-computer interaction. We used observations and log data to evaluate the tool and refine the guidelines. They provide specific guidance for practitioners, as well as a useful framework for additional research in public access interfaces.


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Browne, H., Bederson, B., Plaisant, C., Druin, A. (September 2001)
Designing an Interactive Message Board as a Technology Probe for Family Communication
HCIL-2001-20, CS-TR-4284, UMIACS-TR-2001-63

In this paper, we describe the design issues and technical implementation of an interactive Family Message Board. The Family Message Board enables members of a distributed family to communicate with one another both synchronously and asynchronously via simple, pen-based, digital notes. Each household running this Java-based software can view, create, and manipulate notes in a zoomable space. The Family Message Board will be used as a “technology probe” to help us understand the communication needs of distributed families, and to help us design new devices to meet those needs.


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Konishi, M., Plaisant, C., Shneiderman, B. (July 2001)
Enabling Commuters to Find the Best Route: An Interface for Analyzing Driving History Logs
Proc. Interact 2001, IFIP IOS Press, (2001), 799-800.
HCIL-2001-15, CS-TR-4274, UMIACS-TR-2001-54, ISR-TR-2005-19

This paper describes a prototype interface design for an automobile driving history log. It allows drivers to choose the best route among several alternatives for their common trips. Recorded data includes time to complete the travel, fuel consumption, and number of stops.


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Plaisant, C. (Editor) (June 2001)
2001 Human-Computer Interaction Laboratory Video Reports
HCIL-2001-12, CS-TR-4263, UMIACS-TR-2001-46

45 minute video of the lab's work over this year. Topics are:
  • PhotoFinder Goes Public: Redesigning for the CHI Community
  • PhotoMesa: A Zoomable Image Browser
  • Visual Specification of Queries for Finding Patterns in Time-Series Data
  • Fisheye Menus
  • Visualization for Production Management: Treemap and Fisheye Table Browser
  • Generalizing Query Previews
  • SearchKids: A Digital Library for Children
  • From MusicBlocks to AnimalBlocks: a case study in design
  • Designing the Classroom of the Future
  • Jesterbot: a Storytelling Robot for Pediatric Rehabilitation


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Hornbæk, K., Bederson, B., Plaisant, C. (May 2001)
Navigation Patterns and Usability of Overview+Detail and Zoomable User Interfaces for Maps
Revised version with new title, "Navigation Patterns and Usability of Zoomable User Interfaces with and without an Overview", ACM Transactions on Computer-Human Interaction, Vol. 9, No. 4, pp. 362-389, December 2002.
HCIL-2001-11, CS-TR-4267, UMIACS-TR-2001-48

The literature on information visualizations establishes the usability of overview+detail interfaces, but for zoomable user interfaces, results are mixed. We compare overview+detail and zoomable user interfaces to understand the navigation patterns and usability of these interfaces. Thirty-two subjects solved navigation and browsing tasks on maps organized in one or multiple levels. We find no difference between interfaces in subjects' ability to solve tasks correctly. Eighty percent of the subjects prefer the overview+detail interface, stating that it supports navigation and helps keep track of their position on the map. However, subjects are faster using the zoomable user interface, especially in combination with the multi-level map and when solving navigation tasks. The combination of the zoomable user interface and the multi-level map also improves subjects' recall of objects on the map. Switching between overview and detail windows was correlated with higher task completion time, suggesting that integration of overview and detail windows require mental and motor effort. We found large individual differences in navigation patterns and usability, but subjects' visualization ability influenced usability similarly between interfaces.


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Chipman, L., Plaisant, C., Gahagan, S., Herrmann, J., Hewitt, S., Reaves, L. (April 2001)
Understanding Manufacturing Systems with a Learning Historian for User-Directed Experimentation
HCIL-2001-07, CS-TR-4243, UMIACS-TR-2001-29

This paper describes a learning historian to improve user-directed experimentation with discrete event simulation models of manufacturing systems. In user-directed experimentation, an analyst conducts simulation runs to estimate system performance. Then the analyst modifies the simulation model to evaluate other possibilities. An important characteristic is the ad hoc nature of the experimentation, as the analyst forms and runs new trials based on the results from previous trials. Through user-directed experimentation designers compare alternatives and students learn the relationships between input parameters and performance measures. Recording and reviewing previous trials while using simulation models enhances their benefits, transforming trial-and-error into learning. The learning historian combines a graphical user interface, a discrete event simulation model, and dynamic data visualization. Usability studies indicate that the learning historian is a usable and useful tool because it allows users to concentrate more on understanding system behavior than on operating simulation software.


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Plaisant, C. (Editor) (October 2000)
2000 and 1999-1991 Retrospective: Human-Computer Interaction Laboratory Video Reports
HCIL-2000-24, CS-TR-4196

45 minute video of the lab's work over this year. Topics are:
  • Browsing and annotating digital photographs with Photofinder
  • Learning histories in simulation based learning environments
  • Dynamap
  • StoryRooms


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Plaisant, C., Bhamidipati, P. (October 2000)
Vehicle Speed Information Displays for Public Websites: A Survey of User Preferences
Proceeding of Conference on Intelligent Transportation Systems' 2001 (CD ROM proceedings), ITS'2001, Washington, DC, ITS America, Washington DC, June 2001 (http://www.its.org). Must be printed in color.
HCIL-2000-23, CS-TR-4194, UMIACS-TR-2000-73

The paper reports on a study comparing alternative presentations of freeway speed data on maps. The goal of the study was to inform the design of displays of real time speed data over the Internet to the general public. Subjects were presented with a series of displays and asked to rate their preferences. We looked at different choices of color (3 colors, 6 colors or a continuous range), and proposed line, sensor, and segment representations of the speed data. We also collected feedback on more complex displays such as comparison between current and "normal" speeds, and a chart of speed variation over a period of time at given locations.


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Plaisant, C., Druin, A., Lathan, C., Dakhane, K., Edwards, K., Vice, J., Montemayor, J. (September 2000)
A Storytelling Robot for Pediatric Rehabilitation
Revised version: Proc. ASSETS '00, Washington, Nov. 2000, ACM, New York, 50-55.
HCIL-2000-16, CS-TR-4183, UMIACS-TR-2000-65

We are developing a prototype storytelling robot for use with children in rehabilitation. Children can remotely control a large furry robot by using a variety of body sensors adapted to their disability or rehabilitation goal. In doing so, they can teach the robot to act out emotions (e.g. sad, happy, excited) and then write stories using the storytelling software and include those emotions in the story. The story can then be "played" by the remote controlled robot, which acts out the story and the emotions. We believe that this robot can motivate the children and help them reach their therapy goals through therapeutic play, either by exercising muscles or joints (e.g. for physically challenges children) or by reflecting on the expression of emotions (e.g. for autistic children). We use an innovative design methodology involving children as design partners.


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Tanin, E., Plaisant, C., Shneiderman, B. (May 2000)
Broadening Access to Large Online Databases by Generalizing Query Previews
Proc. of the Symposium on New Paradigms in Information Visualization and Manipulation - CIKM, pp. 80-85, 2000.
HCIL-2000-14, CS-TR-4139, UMIACS-TR-2000-32, ISR-TR-2005-10

Companies, government agencies, and other types of organizations are making their large databases available to the world over the Internet. Current database front-ends do not give users information about the distribution of data. This leads many users to waste time and network resources posing queries that have either zero-hit or mega-hit result sets. Query previews form a novel visual approach for browsing large databases. Query previews supply data distribution information about the database that is being searched and give continuous feedback about the size of the result set for the query as it is being formed. On the other hand, query previews use only a few pre-selected attributes of the database. The distribution information is displayed only on these attributes. Unfortunately, many databases are formed of numerous relations and attributes. This paper introduces a generalization of query previews. We allow users to browse all of the relations and attributes of a database using a hierarchical browser. Any of the attributes can be used to display the distribution information, making query previews applicable to many public online databases.


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Plaisant, C., Komlodi, A. (May 2000)
Evaluation Challenges for a Federation of Heterogeneous Information Providers: The Case of NASA's Earth Science Information Partnerships
IEEE 9th Intl. Workshops on Enabling Technologies (WETICE'2000) Evaluating Collaborative Enterprises, June 14-16, Gaithersburg, MD, pp. 130-138, IEEE, Los Alamitos, CA. http://www.mel.nist.gov/msidevent/workshop/wetice-ece/
HCIL-2000-09, CS-TR-4134, UMIACS-TR-2000-27

NASA's Earth Science Information Partnership Federation is an experiment funded to assess the ability of a group of widely heterogeneous earth science data or service providers to self organize and provide improved and cheaper access to an expanding earth science user community. As it is organizing itself, the federation is mandated to set in place an evaluation methodology and collect metrics reflecting the health and benefits of the Federation. This paper describes the challenges of organizing such a federated partnership self-evaluation and discusses the issues encountered during the metrics definition phase of the early data collection.


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Alborzi, H., Druin, A., Montemayor, J., Sherman, L., Taxén, G., Best, J., Hammer, J., Kruskal, A., Lal, A., Plaisant Schwenn, T., Sumida, L., Wagner, R., Hendler, J. (February 2000)
Designing StoryRooms: Interactive Storytelling Spaces for Children
Proc. ACM Desiging Interactive Systems (DIS'2000), NY, 95-100.
HCIL-2000-02, CS-TR-4106, UMIACS-TR-2000-06

Limited access to space, costly props, and complicated authoring technologies are among the many reasons why children can rarely enjoy the experience of authoring room-sized interactive stories. Typically in these kinds of environments, children are restricted to being story participants, rather than story authors. Therefore, we have begun the development of "StoryRooms," room-sized immersive storytelling experiences for children. With the use of low-tech and high-tech storytelling elements, children can author physical storytelling experiences to share with other children. In the paper that follows, we will describe our design philosophy, design process with children, the current technology implementation and example StoryRooms.


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Plaisant, C. (Editor) (October 2000)
1999 Human-Computer Interaction Laboratory Video Reports
HCIL-99-34, CS-TR-4195

45 minute video of the lab's work over the past year. Topics are:
  • Introduction - Ben Shneiderman
  • Query Previews for EOSDIS
  • Design Space for Data and label Placement for information visualization
  • Understanding the effect of incidents on transportation delays with a simulation based environment
  • Visualizing Legal Information: Hierarchical and Temporal presentations
  • Snap together visualization
  • Designing PETS: A Personal Electronic Teller of Stories
  • Welcome to the HCIL-2 Kids First Kid-Made Video
  • KidPad: A Collaborative Storytelling Environment for Children
  • Softer Software: an excerpt from the Maryland State of Mind program


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Fredrikson, A., North, C., Plaisant, C., Shneiderman, B. (December 1999)
Temporal, Geographical and Categorical Aggregations Viewed through Coordinated Displays: A Case Study with Highway Incident Data
Proceedings of the Workshop on New Paradigms in Information Visualization and Manipulation, Kansas City, Missouri, November 6, 1999 (in conjunction with ACM CIKM'99), ACM New York, 26-34.
HCIL-99-31

Information visualization displays can hold a limited number of data points, typically a few thousand, before they get crowded. One way to solve this problem with larger data sets is to create aggregates. Aggregations were used together with the Snap-Together Visualization system to coordinate the visual displays of aggregates and their content. If two displays each hold one thousand items then rapid access and visibility can be maintained for a million points. This paper presents examples based on a database of highway incident data.


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Harris, C., Allen, R., Plaisant, C., Shneiderman, B. (June 1999)
Temporal Visualization for Legal Case Histories
ASIS'99 Proceedings of the 62nd Annual Meeting of the American Society for Information Sciences, Conference October 31-November 4, 1999, Vol. 36, 271-279.
HCIL-99-18, CS-TR-4047

This paper discusses visualization of legal information using a tool for temporal information called LifeLines. The direct and indirect histories of cases can become very complex. We explored ways that LifeLines could aid in viewing the links between the original case and the direct and indirect histories. The Apple Computer, Inc. v. Microsoft Corporation and Hewlett Packard Company case is used to illustrate the prototype. For example, if users want to find out how the rulings or statutes changed throughout this case, they could retrieve this information within a single display. Using the timeline, users could also choose at which point in time they would like to begin viewing the case. LifeLines support various views of a case's history. For instance, users can view the trial history of a case, the references involved in a case, and citations made to a case. The paper describes improvements to LifeLines that could help in providing a more useful visualization of case history.

Keywords: Graphical user interface, information visualization, legal information, temporal data, history


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Druin, A., Montemayor, J., Hendler, J., McAlister, B., Boltman, A., Fiterman, E., Plaisant, A., Kruskal, A., Olsen, H., Revett, I., Plaisant Schwenn, T., Sumida, L., Wagner, R. (May 1999)
Designing PETS: A Personal Electronic Teller of Stories
Proceedings of CHI'99, Pittsburgh, PA, USA, May 15-20, ACM, New York, 326-329
HCIL-99-13

We have begun the development of a new robotic pet that can support children in the storytelling process. Children can build their own pet by snapping together the modular animal parts of the PETS robot. After their pet is built, children can tell stories using the My Pets software. These stories can then be acted out by their robotic pet. This video paper describes the motivation for this research and the design process of our intergenerational design team in building the first PETS prototypes. We will discuss our progress to date and our focus for the future.


[HTML] [Video] [Link to Report]

Plaisant, C., Rose, A., Rubloff, G., Salter, R., Shneiderman, B. (May 1999)
The Design of History Mechanisms and Their Use in Collaborative Educational Simulations
Proc. of the Computer Support for Collaborative Learning, CSCL' 99, Palo Alto, CA, 348-359.
HCIL-99-11, CS-TR-4027, UMIACS-TR-99-34, ISR-TR-99-74

Reviewing past events has been useful in many domains. Videotapes and flight data recorders provide invaluable technological help to sports coaches or aviation engineers. Similarly, providing learners with a readable recording of their actions may help them monitor their behavior, reflect on their progress, and experiment with revisions of their experiences. It may also facilitate active collaboration among dispersed learning communities. Learning histories can help students and professionals make more effective use of digital library searching, word processing tasks, computer assisted design tools, electronic performance support systems, and web navigation.

This paper describes the design space and discusses the challenges of implementing learning histories. It presents guidelines for creating effective implementations, and the design tradeoffs between sparse and dense history records. The paper also presents a first implementation of learning histories for a simulation-based engineering learning environment called SimPLE (Simulated Processes in a Learning Environment) for the case of a semiconductor fabrication module, and reports on early user evaluation of learning histories implemented within SimPLE.

Keywords: HCI, scaffolding, simulation


[HTML [Video] [Link to Report]

Plaisant, C., Venkatraman, M., Ngamkajornwiwat, K., Barth, R., Harberts, B., Feng, W.
Refining query previews techniques for data with multivalued attributes: The case of NASA EOSDIS
IEEE Forum on Research and Technology Advances in Digital Libraries (ADL '99), IEEE Computer Society, Los Alamitos, CA, 50-59
HCIL-98-17, CS-TR-4010, UMIACS-TR-99-20

Query Previews allows users to rapidly gain an understanding of the content and scope of a digital collection. It uses overviews and previews of abstracted metadata that allows users to perform rapid and dynamic elimination of undesired data. In this paper we present an update on our work developing query previews for a variety of NASA EOSDIS situations. We focused on approaches that successfully address the challenge of multi-valued attribute data while remaining independent of the number of records. We proposed two techniques and showed examples of their use with NASA data.


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Plaisant, C. (Editor) (March 1999)
1998 Human-Computer Interaction Laboratory Video Reports
HCIL-98-16, CS-TR-4007

45 minute video of the lab's work over the past year. Topics are:
  • Introduction - Ben Shneiderman
  • LifeLines: Enhancing Navigation and Analysis of Patient Records
  • SimPLE: Simulated Processes in a Learning Environment
  • Pad++: A Zooming User Interface
  • LinKit: Tight Coupling for Flexible Mutiple-Window Coordination
  • Query Previews for NASA EOSDIS
  • Children as Our Technology Design Partners
  • Genex: An Introduction
  • Genex: A Medical Scenario
  • Human Values for Shaping Educational Technology


[HTML] [Link to Report]

Plaisant, C., Tarnoff, P., Keswani, S., Saraf, A., Rose, A. (October 1998)
Understanding Transportation Management Systems Performance with a Simulation-Based Learning Environment
Proceeding of Conference on Intelligent Transportation Systems' 99, ITS'99, Washington, DC, ITS America, Washington DC, http://www.itsa.org (CD ROM proceedings) 1999.
HCIL-98-10, CS-TR-3947, UMIACS-TR-98-60, ISR-TR-98-59

We have developed a simulation-based learning environment to provide system designers and operators with an appreciation of the impact of incidents on traffic delay. We used an application framework developed at the University of Maryland for constructing simulation-based learning environments called SimPLE (Simulated Processes in a Learning Environment). Environments developed with SimPLE use dynamic simulations and visualizations to represent realistic time-dependent behavior and are coupled with guidance material and other software aids that facilitate learning. The simulation allows learners to close freeway lanes and divert traffic to an arterial road. Users can see the effect of the detour on freeway and arterial delay. Users can then adjust signal timing interactively on a time space diagram and watch the effect of their adjustment on green band changes and on arterial delays and total delays.


[HTML [Video] [Link to Report]

Fekete, J., Plaisant, C. (1998)
Excentric Labeling: Dynamic Neighborhood Labeling for Data Visualization
Proceedings of CHI'99, Pittsburgh, PA, USA, May 15-20, 1999, ACM, New York, 512-519.
HCIL-98-09, CS-TR-3946, UMIACS-TR-98-59

The widespread use of information visualization is hampered by the lack of effective labeling techniques. A taxonomy of labeling methods is proposed. We then describe "excentric labeling", a new dynamic technique to label a neighborhood of objects located around the cursor. This technique does not intrude into the existing interaction, it is not computationally intensive, and was easily applied to several visualization applications. A pilot study indicates a strong speed benefit for tasks that involve the rapid exploration of large numbers of objects.


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Plaisant, C., Mushlin, R., Snyder, A., Li, J., Heller, D., Shneiderman, B. (1998)
LifeLines: Using Visualization to Enhance Navigation and Analysis of Patient Records
Revised version in 1998 American Medical Informatic Association Annual Fall Symposium (Orlando, Nov. 9-11, 1998), p. 76-80, AMIA, Bethesda MD.
HCIL-98-08, CS-TR-3943, UMIACS-TR-98-56

LifeLines provide a general visualization environment for personal histories. We explore its use for clinical patient records. A Java user interface is described, which presents a one-screen overview of a computerized patient record using timelines. Problems, diagnoses, test results or medications can be represented as dots or horizontal lines. Zooming provides more details; line color and thickness illustrate relationships or significance. The visual display acts as a giant menu, giving direct access to the data.


[HTML [Video] [Link to Report]

Li, J., Plaisant, C., Shneiderman, B. (1998)
Data Object and Label Placement for Information Abundant Visualizations
Proceedings, Workshop on New Paradigms in Information Visualization and Manipulation (NPIV'98) In conjunction with the CIKM'98, ACM, New York, 41-48.
HCIL-98-05, CS-TR-3901, UMIACS-TR-98-28, ISR-TR-98-65

Placing numerous data objects and their corresponding labels in limited screen space is a challenging problem in information visualization systems. Extending map-oriented techniques, this paper describes static placement algoritms and develops metrics (such as compactness and labeling rate) as a basis for comparison among these algorithms. A control panel facilitates user customiziation by showing the metrics for alternative algorithms. Dynamic placement techyniques that go beyond map-oriented techniques demonstrate additional possibilities. User actions can lead to selective display of data objects and their labels.


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Tanin, E., Lotem, A., Haddadin, I., Shneiderman, B., Plaisant, C., Slaughter, L. (1998 (Revised 1999))
Facilitating Network Data Exploration with Query Previews: A Study of User Performance and Preference
Behaviour & Information Technology Vol. 19 No. 6 (2000), pp. 393-403.
HCIL-98-02, CS-TR-3879, UMIACS-TR-98-14

Current network data exploration systems which use command languages (e.g. SQL) or form fillin interfaces fail to give users an indication of the distribution of data items. This leads many users to waste time posing queries which have zero-hit or mega-hit result sets. Query previewing is a novel visual approach for browsing huge networked information warehouses. Query previews supply data distribution information about the database that is being searched and give continuo us feedback about the size of the result set for the query as it is being formed. Our within-subjects empirical comparison studied 12 subjects using a form fillin interface with and without query previews. We found statistically significant differences sh owing that query previews sped up performance 1.6 to 2.1 times and led to higher subjective satisfaction.


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Marchionini, G., Plaisant, C., Komlodi, A. (1998)
Interfaces and Tools for the Library of Congress National Digital Library Program
Information Processing & Management, 34, 5, pp. 535-555, 1998. Also French version appeared in Document numerique. 2(1), 1998, pages 53-65, Hermes, Paris.
HCIL-98-01, CS-TR-3872, UMIACS-TR-98-09

This paper describes a collaborative effort to explore user needs in a digital library, develop interface prototypes for a digital library, and suggest and prototype tools for digital librarians and users at the Library of Congress (LC). Interfaces were guided by an assessment of user needs and aimed to maximize interaction with primary resources and support both browsing and analytical search strategies. Tools to aid users and librarians in overviewing collections, previewing objects, and gathering results were created and serve as the beginnings of a digital librarian toolkit. The design process and results are described and suggestions for future work are offered.


[HTML] [Link to Report]

Plaisant, C. (Editor) (March 1999)
1997 Human-Computer Interaction Laboratory Video Reports
HCIL-97-22, CS-TR-4006

45 minute video of the lab's work over the past year. Topics are:
  • Introduction - Ben Shneiderman
  • Bringing treasures to the surface
  • Viewing websites using a hierarchical table of contents browser
  • Elastic Windows
  • Using multimedia learning resources for the Baltimore Learning Community
  • Visual data mining using Spotfire
  • Relate-Create-Donate
  • Query previews in networked information systems
  • As others see us: HCIL & the Teaching/Learning Theater Extract from "Your ticket to technology: Beyond the horizon"


[HTML] [Link to Report]

Greene, S., Tanin, E., Plaisant, C., Shneiderman, B., Olsen, L., Major, G., Johns, S. (1997)
The End of Zero-Hit Queries: Query Previews for NASA's Global Change Master Directory
International Journal Digital Libraries Vol. 2 No.2+3 (1999), pp.79-90
HCIL-97-20, CS-TR-3856, UMIACS-TR-97-84

The Human-Computer Interaction Laboratory (HCIL) of the University of Maryland and NASA have collaborated over the last three years to refine and apply user interface research concepts developed at HCIL in order to improve the usability of NASA data services. The research focused on dynamic query user interfaces, visualization, and overview +preview designs. An operational prototype, using query previews, was implemented with NASA's Global Change Master Directory (GCMD), a directory service for earth science data sets. Users can see the histogram of the data distribution over several attributes and choose among attribute values. A result bar shows the cardinality of the result set, thereby preventing users from submitting queries that would have zero hits. Our experience confirmed the importance of metadata accuracy and completeness. The query preview interfaces make visible problems or holes in the metadata that are unnoticeable with classic form fill-in interfaces. This could be seen as a problem, but we think that it will have a long-term beneficial effect on the quality of the metadata as data providers will be compelled to produce more complete and accurate metadata. The adaptation of the research prototype to the NASA data required revised data structures and algorithms.


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Plaisant, C., Shneiderman, B., Mushlin, R. (1997)
An Information Architecture to Support the Visualization of Personal Histories
Information Processing & Management, 34, 5, pp. 581-597, 1998.
HCIL-97-19, CS-TR-3855, UMIACS-TR-97-87

This paper proposes an information architecture for personal history data and describes how the data model can be extended to a runtime model for an intuitive visualization using graphical timelines. Our information architecture, is developed for medical patient records, but is usable in other application domains such as juvenile justice or personal resumes. Our model of personal history data groups events into aggregates which are contained in facets (e.g. doctor visits, hospitalizations, or lab tests). Links enable representation of arbitrary relationships across events and aggregates. Data attributes such as severity can be mapped by data administrators to visual attributes such as color and line thickness. End-users have powerful controls over the display contents and they can modify the mapping to fit their tasks.


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Greene, S., Marchionini, G., Plaisant, C., Shneiderman, B. (1997)
Previews and Overviews in Digital Libraries: Designing Surrogates to Support Visual Information-Seeking
Journal of the American Society for Information Science 51, 3 (March 2000), 380-393.
HCIL-97-16, CS-TR-3838, UMIACS-TR-97-73, ISR-TR-97-80

To aid designers of digital library interfaces and web sites in creating comprehensible, predictable and controllable environments for their users, we define and discuss the benefits of previews and overviews as visual information representations. Previews and overviews are graphic or textual representations of information abstracted from primary information objects. They serve as surrogates for those objects. When utilized properly, previews and overviews allow users to rapidly discriminate objects of interest from those not of interest, and to more fully understand the scope and nature of large collections of information resources. We provide a more complete definition of previews and overviews, and discuss system parameters and aspects of primary information objects relevant to designing effective preview and overviews. Finally, we present examples that illustrate the use of previews and overviews and offer suggestions for designers.


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Alonso, D., Rose, A., Plaisant, C., Norman, K. (1997)
Viewing Personal History Records: A Comparison of Tabular Format and Graphical Presentation Using LifeLines
Behavior and Information Technology 17, 5, 1998, 249-262.
HCIL-97-13, CS-TR-3795, UMIACS-TR-97-45

Thirty-six participants used a static version of either LifeLines, a graphical interface, or a Tabular representation to answer questions about a database of temporal personal history information. Results suggest that overall the LifeLines representation led to much faster response times, primarily for questions which involved interval comparisons and making intercategorical connections. In addition, on a follow-up questionnaire, nine out of eleven questions rated LifeLines preferable in terms of user satisfaction. A "first impression"test showed that LifeLines can reduce some of the biases of the tabular record summary. A post-experimental memory test led to significantly (p<.004) higher recall for LifeLines. Finally, simple interaction techniques are proposed to augment LifeLines ability to better deal with precise dates, attribute coding and overlaps.


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Nation, D., Plaisant, C., Marchionini, G., Komlodi, A. (May 1997)
Visualizing Websites Using a Hierarchical Table of Contents Browser: WebTOC
Proceedings of 3rd Conference on Human Factors and the Web, Denver, Colorado, June 12, 1997.
HCIL-97-10, CS-TR-3791, UMIACS-TR-97-41, CLIS-TR-97-08

A method is described for visualizing the contents of a Web site with a hierarchical table of contents using a Java program and applet called WebTOC. The automatically generated expand/contract table of contents provides graphical information indicating the number of elements in branches of the hierarchy as well as individual and cumulative sizes. Color can be used to represent another attribute such as file type and provide a rich overview of the site for users and managers of the site. Early results from user studies suggest that WebTOC is easily learned and can assist users in navigating websites.


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Doan, K., Plaisant, C., Shneiderman, B., Bruns, T. (1997)
Interface and Data Architecture for Query Preview in Networked Information Systems
ACM Transactions on Information Systems, July 1999, Vol. 17, No. 3, 320-341. A short early version also appeared in ACM SIGMOD Record, Vol.26, No.1, pp. 75-81 March 1997, as Query Previews for Networked Information Systems: A Case Study with NASA Environmental Data by Doan, K., Plaisant, C., Shneiderman, B., Bruns, B.
HCIL-97-09, CS-TR-3792, UMIACS-TR-97-42, ISR-TR-97-57

There are numerous problems associated with formulating queries on networked information systems. These include data diversity, data complexity, network growth, varied user base, and slow network access. This paper proposes a new approach to a network query user interface which consists of two phases: query preview and query refinement. This new approach is based on the concepts of dynamic queries and query previews, which guides users in rapidly and dynamically eliminating undesired datasets, reducing the data volume to manageable size, and refining queries locally before submission over a network. Examples of 2 applications are given: a Restaurant Finder and prototype with NASA's Earth Observing Systems--Data Information Systems (EOSDIS). Data architecture is discussed and user's feedback is presented. Dynamic queries and query previews provide solutions to many existing problems in querying networked information systems.


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Doan, K., Plaisant, C., Shneiderman, B., Bruns, T. (1997)
Query Previews for Networked Information Systems: A Case Study with NASA Environmental Data
ACM SIGMOD Record, Vol. 26, No. 1 (75-81), March 1997
HCIL-97-02

Formulating queries on networked information systems is laden with problems: data diversity, data complexity, network growth, varied user base, and slow network access. This paper proposes a new approach to a network query user interface which consists of two phases: query preview and query refinement. This new approach is based on dynamic queries and tight coupling, guiding users to rapidly and dynamically eliminate undesired items, reduce the data volume to a manageable size, and refine queries locally before submission over a network. A two-phase dynamic query system for NASAüs Earth Observing Systems--Data Information Systems (EOSDIS) is presented. The prototype was well received by the team of scientists who evaluated the interface.

Keywords: User interface, direct manipulation, dynamic query, metadata, query preview, query refinement, EOSDIS.


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Plaisant, C., Bruns, T., Shneiderman, B., Doan, K. (1996)
Query Previews in Networked Information Systems: the Case of EOSDIS
Video in CHI 97 Video program , Atlanta GA, 22-27 March 1997, ACM, New York NY. A two page summary also appears in CHI 97 Extended Abstracts, ACM New York, 202-203.
HCIL-96-19

Dynamic queries have been shown to be an effective technique to browse information, and to find patterns and exceptions. Dynamic queries involve theinteractive control by a user of visual query parameters that generate rapid (100 ms update), animated, and visual displays of database search results. The data of early implementations was stored in local memory to guarantee optimal speed. Problems arise when the data is very large and distributed over a network. To overcome the problems of slow networks and data volume we propose a two-phase approach to query formulation using query previews and query refinements. Preview mechanisms have been used in the past and we believe that their use will be a ajor component of successful networked information systems interfaces.
This video is also available from HCIL as part of the 1996 HCIL Video report.


[HTML] [Video] [Link to Report]

Plaisant, C., Marchionini, G., Bruns, T., Komlodi, A., Campbell, L. (October 1996)
Bringing Treasures to the Surface: Iterative Design for the Library of Congress National Digital Library Program
CHI 97 Proceedings, Atlanta GA, 22-27 March 1997, ACM New York, 518-525
HCIL-96-16, CS-TR-3694, CLIS-TR-96-03

The Human-Computer Interaction Lab worked with a team of the Library of Congress (LC) to develop and test interface designs for LCUs National Digital Library Program. Three iterations are described and illustrate the progression of the design toward a compact design that minimizes scrolling and jumping and anchors users in a screen space that tightly couples search and results. Issues and resolutions are discussed for each iteration and reflect the challenges of incomplete metadata, data visualization, and the rapidly changing web environment.


[Video] [Link to Report]

Ellis, J., Rose, A., Plaisant, C. (September 1996)
Putting Visualization to Work: ProgramFinder for Youth Placement
CHI 97 Proceedings, Atlanta GA, 22-27 March 1997, ACM New York, 502-509
HCIL-96-15, CS-TR-3692

The Human-Computer Interaction Laboratory (HCIL) and the Maryland Department of Juvenile Justice (DJJ) have been working together to develop the ProgramFinder,a tool for choosing programs for a troubled youth from drug rehabilitation centers to secure residential facilities. The seemingly straightforward journey of the ProgramFinder from an existing user interface technique to a product design required the development of five different prototypes which involved user interface design, prototype implementation, and selecting search criterion. While HCIL's effort focused primarily on design and implementation, DJJ's attribute selection process was the most time consuming and difficult task. We also found that a direct link to DJJ's workflow was needed in the prototypes to generate the necessary "buy-in". This paper analyzes the interaction between the efforts of HCIL and DJJ and the amount of "buy-in" by DJJ staff and management. Lessons learned are presented for developers.


[HTML] [Link to Report]

Plaisant, C. (Editor) (June 1996)
1996 Human-Computer Interaction Laboratory Video Reports
HCIL-96-12, CS-TR-3664

45 minute video of the lab's work over the past year. Topics are:
  • Introduction - Ben Shneiderman
  • Elastic Windows for Rapid Window Management
  • Life-Lines: Visualizing Personal Histories
  • Designing Interfaces for Youth Services Information Management
  • Query Previews in Networked Information Systems: The case of EOSDIS
  • Baltimore Learning Communities
  • Sample from '94 Video Report - Visual Information Seeking using the FilmFinder


[HTML] [Link to Report]

Marchionini, G., Plaisant, C., Komlodi, A. (May 1996)
User Needs Assessment for the Library of Congress National Digital Library
HCIL-96-09, CS-TR-3640, CAR-TR-829, CLIS-96-01


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Rose, A., Ellis, J., Plaisant, C., Greene, S. (May 1996)
Life Cycle of User Interface Techniques: The DJJ Information System Design Process
HCIL-96-07, CS-TR-3637, CAR-TR-826

To take advantage of today's technology, many organizations are migrating from their legacy systems. With help from the Human-Computer Interaction Laboratory (HCIL) and Cognetics Corporation, the Maryland Department of Juvenile Justice (DJJ) is currently undergoing an effort to redesign their information system to take advantage of graphical user interfaces. As a research lab, HCIL identifies interesting research problems and then prototypes solutions. As a project matures, the exploratory prototypes are adapted to suit the end product requirements. This case study describes the life cycle of three DJJ prototypes: (1) LifeLines, which uses time lines to display an overview of a youth in one screen, (2) the DJJ Navigator, which helps manage individual workloads by displaying different user views, and (3) the ProgramFinder, a tool for selecting the best program for a youth.


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Plaisant, C., Rose, A. (March 1996)
Exploring LifeLines to Visualize Patient Records
A short version of this report appeared as a poster summary in 1996 American Medical Informatic Association Annual Fall Symposium (Washington, DC, Oct. 26-30, 1996), pp. 884, AMIA, Bethesda MD.
HCIL-96-04, CS-TR-3620, CAR-TR-819

LifeLines provide a general visualization environment for personal histories. We explored its use for medical patient records. A one screen overview of the record using timelines provides direct access to the data. Problems, hospitalization and medications can be represented as horizontal lines, while icons represent discrete events such as physician consultations (and progress notes) or tests. Line color and thickness can illustrate relationships or significance. Techniques are described to display large records. Rescaling tools and filters allow users to focus on part of the information, revealing more details.


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Plaisant, C., Levy, R., Zhao, W. (November 1995)
BizView: Managing Business and Network Alarms
Summary of the video available from HCIL as part of the 1995 HCIL Video report.
HCIL-95-22

We demonstrate a network monitoring prototype incorporating both physical network alarms (e.g., a node is down) and logical alarms generated by sensors in the business applications running on the network (inventory too low or too high, excessive number of orders, etc.). Our BizView Enterprise Monitoring prototype provides tightly coupled filtered views of the network's current status and past history, timelines of alarm overviews and traditional textual details. Filtering attributes are modified interactively to deal with temporary needs or alarm overflows.


[HTML] [Link to Report]

North, C., Shneiderman, B., Plaisant, C. (October 1995)
User Controlled Overviews of an Image Library: A Case Study of the Visible Human
Proc. of the 1st ACM International Conference on Digital Libraries (Bethesda, MD, March 20-23, 1996) 74-82. ACM, New York. In addition a video "Browsing anatomical image databases: A case study of the Visible Human" appeared in CHI 96 Video Program with a two-page video summary in ACM CHI '96 Conference Companion (Vancouver, BC, Canada, April 13-18, 1996) 414-415, http://www.acm.org/sigchi/chi96/proceedings. The video is also available from HCIL as part of the 1995 HCIL Video report.
HCIL-95-20, CS-TR-3550, CAR-TR-798, ISR-TR-95-99.

This paper proposes a user interface for remote browsing of the Visible Human digital image library from the National Library of Medicine. The interface presents the user with a pair of tightly coupled views into the data set. The overview image provides a global view of the overall search space, and the preview image provides details about high resolution images available for downloading. The user sweeps the views through the search space and receives smooth, rapid feedback of contents. The interface software is completely functional and is freely available for public use at http://www.nlm.nih.gov.


[HTML] [Video] [Link to Report]

Plaisant, C. (Editor) (June 1995)
1995 Human-Computer Interaction Laboratory Video Reports
HCIL-95-17, CS-TR-3532, CAR-TR-795

49 minute video of the labs work over the past year. Topics are:
  • Introduction and table of contents - Ben Shneiderman
  • Using Dynamic Queries for Youth Services Information - Anne Rose, Ajit Vanniamparampil
  • Life-Lines: Visualizing Personal Histories - Brett Milash, Catherine Plaisant, Anne Rose
  • Dynamic Queries and Pruning for Large Tree Structures - Harsha Kumar
  • Browsing Anatomical Image Databases : the Visible Human - Flip Korn, Chris North
  • Spinning Your Web: WWW Interface Design Issues - Vince Boisselle
  • BizView : Managing Business and Network Alarms - Catherine Plaisant, Wei Zhao and Rina Levy
  • Animated Specifications Using Interaction Object Graphs - David Carr
  • WinSurfer: Treemaps for Replacing the Windows File Manager - Marko Teittinen


[HTML] [Link to Report]

Doan, K., Plaisant, C., Shneiderman, B. (September 1995)
Query Previews in Networked Information Systems
Proc. of the Third Forum on Research and Technology Advances in Digital Libraries, ADL '96 (Washington, DC, May 13-15, 1996) IEEE CS Press, 120-129. Also abstract appears as Architecture of dynamic query user interface for networked information systems in on-line Proc. of NASA Science Information Systems Interoperability Conference (College Park, MD, Nov. 6-9, 1995)
HCIL-95-16, CS-TR-3524, CAR-TR-788, ISR-TR-95-90

In a networked information system, there are three major obstacles facing users in a querying process: slow network performance, large data volume and data complexity. In order to overcome these obstacles, we propose a two-phase approach to query formulation: Query Preview and Query Refinement. In the Query Preview phase, users formulate an initial query by selecting desired attribute values. The volume of matching data sets is shown graphically on preview bars which aid users to rapidly eliminate undesired data sets, and focus on a manageable number of relevant data sets. Query previews also prevent wasted steps by eliminating zero-hit queries. When the estimated number of data sets is low enough, users submit the initial query to the network, which returns the metadata of the data sets for the Query Refinement phase. Using this approach, we developed dynamic query user interfaces allowing users to formulate their queries using direct manipulation in an exploratory manner across a networked enviroment.


[HTML] [Link to Report]

Plaisant, C., Milash, B., Rose, A., Widoff, S., Shneiderman, B. (September 1995)
Life Lines: Visualizing Personal Histories
ACM CHI '96 Conference Proc. (Vancouver, BC, Canada, April 13-18, 1996) 221-227, color plate 518, http://www.acm.org/sigchi/sigchi96/proceedings. The paper also has a corresponding video in the CHI 96 Video Program ACM, New York. Video also available from HCIL in the 1996 HCIL Video report.
HCIL-95-15, CS-TR-3523, CAR-TR-787, ISR-TR-95-88.

Life Lines provide a general visualization environment for personal histories that can be applied to medical and court records, professional histories and other types of biographical data. A one screen overview shows multiple facets of the records. Aspects, for example medical conditions or legal cases, are displayed as individual time lines, while icons indicate discrete events, such as physician consultations or legal reviews. Line color and thickness illustrate relationships or significance, scaling tools and filters allow users to focus on part of the information. Life lines reduce the chances of missing information, facilitate spotting anomalies and trends, streamline access to details, while remaining tailorable and easily sharable between applications. The paper describes the use of Life Lines for youth records of the Maryland Department of Juvenile Justice.and also for medical records. Techniques to deal with complex records are reviewed and issues of a standard personal record format are discussed.


[HTML] [Link to Report]

Kumar, H., Plaisant, C., Shneiderman, B. (March 1995)
Browsing Hierarchical Data with Multi-Level Dynamic Queries and Pruning
International Journal of Human-Computer Studies, Volume 46, No. 1, 103-124 (January 1997).
HCIL-95-12, CS-TR-3474, CAR-TR-772, ISR-TR-95-53.

Users often must browse hierarchies with thousands of nodes in search of those that best match their information needs. The PDQ Tree-browser (Pruning with Dynamic Queries) visualization tool was specified, designed and developed for this purpose. This tool presents trees in two tightly-coupled views, one a detailed view and the other an overview. Users can use dynamic queries, a method for rapidly filtering data, to filter nodes at each level of the tree. The dynamic query panels are user-customizable. Subtrees of unselected nodes are pruned out, leading to compact views of relevant nodes. Usability testing of the PDQ Tree-browser, done with 8 subjects, helped assess strengths and identify possible improvements. The PDQ Tree-browser was used in Network Management (600 nodes) and UniversityFinder (1100 nodes) applications. A controlled experiment, with 24 subjects, showed that pruning significantly improved performance speed and subjective user satisfaction. Future research directions are suggested.


[HTML] [Link to Report]

Plaisant, C., Shneiderman, B. (May 1995)
Organization Overviews and Role Management: Inspiration for Future Desktop Environments
IEEE Proc. 4th Workshop on Enabling Technologies: Infrastructure for Collaborative Enterprises (Berkeley Springs, WV, April 20-22, 1995) 14-22.
HCIL-95-11, CS-TR-3473, CAR-TR-771.

In our exploration of future work environments for the World Bank we propose two concepts. Organization overviews provide a consistent support to present the results of a variety of manual or semi-automated searches. This view can be adapted or expanded for each class of users to finally map the multiple personal roles an individual has in an organization. After command line interfaces, graphical point and click interfaces, and the current "docu-centric" designs, the natural direction is towards a role-centered approach where we believe the emphasis is on the management of those multiple roles. Each role involves coordination with groups of people and accomplishment of tasks within a schedule.


[HTML] [Link to Report]

Plaisant, C., Rose, A., Shneiderman, B., Vanniamparampil, A. (Revised October 1996)
User Interface Reengineering: Low Effort, High Payoff Strategies
IEEE Software, vol.14, 4 (July/August 1997) 66-72. Also translated in Japanese in Nikkei Computer,Nikkei Business Publications, Inc., Tokyo, Japan, no. 430, pp. 151-159, Nov. 1997.
HCIL-95-08, CS-TR-3459, CAR-TR-767

User interface technology has advanced rapidly in recent years. Incorporating new developments in existing systems could result in substantial improvements in usability, thereby improving performance and user satisfaction, while shortening training and reducing error rates. Our focus is on low-effort high-payoff improvements to aspects such as data display and entry, consistency, messages, documentation, and system access. This paper provides guidelines for managers and designers responsible for user interface reengineering, based on the experience we gained from six projects, and compiles our observations, recommendations and outcomes.


[HTML] [Link to Report]

Rose, A., Shneiderman, B., Plaisant, C. (February 1995)
An Applied Ethnographic Method for Redesigning User Interfaces
ACM Proc. of DIS 95, Symposium on Designing Interactive Systems: Processes, Practices, Methods & Techniques (Ann Arbor, MI, Aug 23-25, 1995)115-122.
HCIL-95-07, CS-TR-3454, CAR-TR-765.

Methods for observing software users in the workplace will become increasingly important as the number of people using computers grows and developers improve existing systems. Successful redesigns rely, in part, on complete and accurate evaluations of the existing systems. Based on our evaluation experience, we have derived a set of practical guidelines to be used by designers in preparing for the evaluation, performing the field study, analyzing the data, and reporting the findings. By providing a general framework based on ethnographic research, we hope to reduce the likelihood of some common problems, such as overlooking important information and misinterpreting observations. Examples from our ongoing work with the Maryland Department of Juvenile Services are used to illustrate the proposed guidelines.


[HTML] [Link to Report]

Plaisant, C., Shneiderman, B. (May 1995)
Organization Overviews and Role Management: Inspiration for Future Desktop Environments
Video in CHI '95 Video Program, ACM, New York. A two page video summary also appears in ACM CHI '95 Conference Companion, (Denver, Colorado, May 7-11, 1995) 419-420. Video also available through HCIL as part of the 1994 HCIL Video Report.
HCIL-95-03

We worked with the World Bank, a large international organization, to look at desktop environments of the near future. We chose to focus on a subset of problems that employees regularly have to struggle with:
  • finding people who can help
  • searching documents and resources
  • juggling many roles (e.g. a person can be in charge of three projects, member of two task forces, editor of the bank magazine, and organizer of the holiday party.)
A great deal of personal organization is required to manage these roles whose goals, partners, tools and documents are likely to be very different. The previous research on role theory [1] or CSCW focuses mainly on the coordination of individuals while our goal is to assist individuals manage their multiple roles.


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Atallah, G., Ball, M., Baras, J., Goli, S., Karne, R., Kelley, S., Kumar, H., Plaisant, C., Roussopoulos, N., Shneiderman, B., Srinivasarao, M., Stathatos, K., Teittinen, M., Whitefield, D.
Next Generation Network Management Technology
ISR-TR-94-42 Proceedings of the 12th Symposium on Space Nuclear Power and Propulsion/Commercialization, pp. 75-82, Albuquerque, NM, January 8-12, 1995.
HCIL-94-19

Today's telecommunications networks are becoming increasingly large, complex, mission critical and heterogeneous in several dimensions. For example, the underlying physical transmission facilities of a given network may be "mixed media" (copper, fiber-optic, radio, and satellite); the sub networks may be acquired from different vendors due to economic, performance, or general availability reasons; the information being transmitted over the network may be "multimedia" (video, data, voice, and images) and, finally, varying performance criteria may be imposed e.g. data transfer may require high throughput while the others, whose concern is voice communications, may require low call blocking probability. For these reasons, future telecommunications networks are expected to be highly complex in their services and operations. Due to this growing complexity and the disparity among management systems for individual sub networks, efficient network management systems have become critical to the current and future success of telecommunications companies. This paper addresses a research and development effort which focuses on prototyping configuration management, since that is the central process of network management and all other network management functions must be built upon it. Our prototype incorporates ergonomically designed graphical user interfaces tailored to the network configuration management subsystem and to the proposed advanced object-oriented database structure. The resulting design concept follows open standards such as Open Systems Interconnection (OSI) and incorporates object oriented programming methodology to associate data with functions, permit customization, and provide an open architecture environment.


 [Link to Report]

Plaisant, C. (Editor) (June 1994)
1994 Human-Computer Interaction Laboratory Video Reports
HCIL-94-17, CS-TR-3531, CAR-TR-794.

80 minutes of video demonstrations from the past year's research. Topics are:
  • Introduction and table of contents - Ben Shneiderman, [3:18]
  • Visual information seeking using the FilmFinder - Christopher Ahlberg, Ben Shneiderman, [6:12]
  • Organization overviews and role management-Inspiration for future desktop environments - Catherine Plaisant, Ben Shneiderman, [9:39]
  • Visual decision-making: using treemaps for the analytic hierarchy process - Toshiyuki Asahi, Ben Shneiderman, David Turo, [8:34]
  • Visual information management for satellite network configuration - Catherine Plaisant, Harsha Kumar, Marko Teittinen, Ben Shneiderman, [8:49]
  • Graphical macros: a technique for customizing any application using pixel-pattern matching-Richard Potter, [9:49]
  • Education by engagement and construction: can distance learning be better than face to face?- Ben Shneiderman, [15:00]
  • Dynamic queries demos: revised HomeFinder and text version plus health statistics atlas-Ben Shneiderman, [9:40]
  • Dynamic Queries are user controlled displays of visual or textual information. Ben Shneiderman presents the HomeFinder (developed by Chris Williamson), followed by the text version (Vinit Jain) and the Health Statistics Atlas (Catherine Plaisant and Vinit Jain).
  • CHI '94 slide and video show- [9:12]


[HTML] [Link to Report]

Plaisant, C., Jain, V. (April 1994)
Dynamaps: Dynamic Queries on a Health Statistics Atlas
Video in CHI '94 Video Program, ACM, New York. A two page video summary also appears in ACM CHI '94 Conference Companion, (Boston, MA, April 24-28, 1994) 439-440. Video also available through HCIL as part of the 1993 HCIL Video Report.
HCIL-94-16

Dynamic queries are user-controlled animated displays of visual or textual data. On an application developed for the National Center for Health Statistics and running on their ordinary staff equipment, a thematic map of the United States is animated by moving a time slider to illustrate trends of mortality rates. Other sliders filter parts of the maps interactively according to parameters such as demographics. During the filtering possible correlations can be observed as they create color patterns in he "dissapearance" of the states. This application has been received with enthusiasm by the user community and will be distributed with selected new datasets.


[HTML [Video] [Link to Report]

Kumar, H., Plaisant, C., Teittinen, M., Shneiderman, B. (June 1994)
Visual information management for network configuration
Part of this article was later published in: Next Generation Network Management Technology, G. Atallah, M. Ball, J. Baras, S. Goli, R. Karne, S. Kelley, H. Kumar, C. Plaisant, N. Roussopoulos, B. Shneiderman, M. Srinivasarao, K. Stathatos, M. Teittinen, and D. Whitefield, Proceedings of the 12th Symposium on Space Nuclear Power and Propulsion/Commercialization, pp. 75-82, Albuquerque, NM, January 8-12, 1995
HCIL-94-07, CS-TR-3288, CAR-TR-716, ISR-TR-94-45

Current network management systems rely heavily on forms in their user interfaces. The interfaces reflect the intricacies of the network hardware components but provide little support for guiding users through tasks. There is a scarcity of useful graphical visualizations and decision-support tools. We applied a task-oriented approach to design and implemented the user interface for a prototype network configuration management system. Our user interface provides multiple overviews of the network (with potentially thousands of nodes) and the relevant configuration tasks (queries and updates). We propose a unified interface for exploration, querying, data entry and verification. Compact color-coded treemaps with dynamic queries allowing user-controlled filtering and animation of the data display proved well-suited for representing the multiple containment hierarchies in networks. Our Tree-browser applied the conventional node-link visualization of trees to show hardware containment hierarchies. Improvements to conventional scrollbar-browsers included tightly coupled overviews and detailed views. This visual interface, implemented with Galaxy and the University of Maryland Widget Library TM, has received enthusiastic feedback from the network management community. This application-specific paper has design paradigms that should be useful to designers of varied systems.


[HTML] [Link to Report]

Shneiderman, B., Plaisant, C. (May 1994)
The Future of Graphic User Interfaces: Personal Role Managers
People and Computers IX, British Computer Society's HCI 94 (Glasgow, Scotland, Aug. 1994) CU Press (Cambridge, U.K.) 3-8.
HCIL-94-05, CS-TR-3285, CAR-TR-713, ISR-TR-94-48

Personal computer users typically manage hundreds of directories and thousands of files with hierarchically structured file managers, plus archaic cluttered-desktop window managers, and iconic representations of applications. These users must deal with the annoying overhead of window housekeeping and the greater burden of mapping their organizational roles onto unnecessarily rigid hierarchy. An alternate approach is presented, Personal Role Manager (PRM), to structure the screen layout and the interface tools to better match the multiple roles that individuals have in an organization. Each role has a vision statement, schedule, hierarchy of tasks, set of people, and collection of documents.


[HTML [Link to Report]

Carr, D., Plaisant, C., Hasegawa, H. (revised June 1995)
Usability Experiments for the Redesign of a Telepathology Workstation
Based on The Design of a Telepathology Workstation: Exploring Remote Images. Interacting with Computers, 11(1), 1998, pp. 33-52.
HCIL-94-03, CS-TR-3270, CAR-TR-708

Dynamic telepathology uses a remotely controlled microscope to allow a pathologist to view samples at a remote location. However, time delays introduced by remote operation have made use of a commercial dynamic telepathology system difficult and frustrating. This paper describes experiments to evaluate and redesign the user interface. We also make recommendations for further automation to support the pathology process and increase the usefulness of the system.


[Link to Report]

Plaisant, C., Carr, D., Shneiderman, B. (April 1994)
Image Browsers: Taxonomy, Guidelines, and Informal Specifications
IEEE Software, vol.12, 2 (March 1995) 21-32.
HCIL-94-02, CS-TR-3282, CAR-TR-712, ISR-TR-94-39

Image browsing is necessary in numerous applications. Designers have merely used two one-dimensional scroll bars or they have made ad hoc designs for a two-dimensional scroll bar. However, the complexity of two-dimensional browsing suggests that more careful analysis, design, and evaluation might lead to significant improvements. We present a task taxonomy for image browsing, suggest design features and guidelines, assess existing strategies, and introduce an informal specification technique to describe the browsers.


[HTML] [Link to Report]

Plaisant, C. (Editor) (June 1993)
1993 Human-Computer Interaction Laboratory Video Reports
HCIL-93-25, CS-TR-3530, CAR-TR-793

  • Introduction and table of contents - Ben Shneiderman, [4:00]
  • Dynamaps: dynamic queries on a health statistics atlas - Catherine Plaisant and Vinit Jain, [6:34]
  • Hierarchical visualization with Treemaps: making sense of pro basketball data - Dave Turo, [10:47]
  • TreeViz: file directory browsing - Brian Johnson, [10:04]
  • HyperCourseware: computer integrated tools in the AT&T Teaching Theater - Kent Norman, [7:08]
  • Improving access to medical abstracts: Grateful Med Interface prototype - Gary Marchionini, [6:08]
  • Layout appropriateness: guiding interface design with simple task descriptions - Andrew Sears, [4:00]


[HTML] [Link to Report]

Plaisant, C., Carr, D., Hasegawa, H. (April 1993)
Exploring Remote Images: A Telepathology Workstation
Video in ACM INTERCHI 93 Video Program (Amsterdam, Netherlands, April 24-29, 1993), video available through ACM SIGGRAPH Video Review, issue 88-89. A one page summary also appears in INTERCHI 93 Proceedings, 518. Video also available through HCIL as part of the 1992 HCIL Video Report.
HCIL-93-24

Telemedicine is the practice of medicine over communication links. The physician being consulted and the patient are in two different locations. A first telepathology system has been developed by Corabi Telemetrics. It allows a pathologist to render a diagnosis by examining tissue samples or body fluids under a remotely located microscope. Of course it would seem natural to digitize the entire specimen at the highest magnification and then leisurely explore the transmitted image. But this is not currently practical because the specimens are very high definition 3D color objects requiring too long to digitize and having impractical storage requirements. Therefore the specimen still needs today to be explored under a microscope.


[HTML [Link to Report]

Plaisant, C. (Aug. 1993)
Facilitating Data Exploration: Dynamic Queries on a Health Statistics Map
ASA (Alexandria, VA)1993 Proc. of the Annual Meeting of the American Statistical Association of the Government Statistics Section (San Francisco, CA, Aug. 1993) 18-23.
HCIL-93-21

Users with no specialized computer training are often discouraged by the complex syntax of query languages and the output of long tables of alphanumerical values. The Human-Computer Interaction Laboratory has recently developed the concept of dynamic queries which allows user control of animated visual displays of information. Experiments with our first applications have shown that dynamic queries can help reveal trends or global properties as well as assist users in answering specific questions. We present a new application developed with the National Center for Health Statistics and running on a simple PC. A thematic map of the United States is animated by adjusting sliders displayed on the side of the map. A time slider illustrates time trends. The other sliders control the filtering out of areas of the map according to parameters such as demographics. Detailed data about a particular area is obtained by clicking directly on its location on the map. We have received encouraging feedback from use rs. We also hypothesize that this new tool will facilitate the finding of confounders.


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Shneiderman, B. (1993)
Preface to Sparks of Innovation in Human-Computer Interaction
Sparks of Innovation in Human-Computer Interaction, B. Shneiderman, Ed., Ablex Publ. (1993) 385 pages. ACM Interactions, vol. 1, 1 (Jan. 1994) 67-71.
HCIL-93-13

The occasion for this book is the 10th Anniversary of the Human-Computer Interaction Laboratory (HCIL) at the University of Maryland. I have selected two dozen key papers from more than a hundred to repersent the work of many participants. My section introductions tell how we do what we do, including some of our failures and background stories that are not appropriate for journal papers. Many papers are trimmed to emphasize the cogent points. They weave together the threads of our work into a unified fabric that reveals the patterns of developement. It was difficult to choose the best papers; these exemplify different research method-ologies and show the maturation of thuman-computer interaction research. This book is a tribute to the faculty, staff, visitors, and students who have shared in a decade of work.

Contents
Preface
Overview: fuel for a new discipline
Introduction: supporting the process of innovation
1. Direct manipulation
1.1 Direct manipulation: a step beyond programming languages, Ben Shneiderman
1.2 A study of file manipulation by novices using commands vs. direct manipulation, Sepeedeh Margono, Ben Shneiderman
1.3 Remote direct manipulation: a case study of a telemedicine workstation, Richard Keil-Slawik, Catherine Plaisant, Ben Shneiderman
2. Menu selection
2.1 Embedded menus: selecting items in context, Larry Koved, Ben Shneiderman
2.2 An empirical comparison of pie vs. linear menus, Jack Callahan Don Hopkins, Mark Weiser, Ben Shneiderman
2.3 Time stress effects on two menu selection systems, Daniel F. Wallace, Nancy S. Anderson, Ben Shneiderman
3. Hypertext
3.1 Finding facts vs. browsing knowledge in hypertext systems, Gary Marchionini, Ben Shneiderman
3.2 Restructuring knowledge for an electronic encyclopedia, Charles B. Kreitzberg, Ben Shneiderman
3.3 The Electronic Teaching Theater: interactive hypermedia & mental models of the classroom, Kent L. Norman
4. Touchscreens
4.1 Improving the accuracy of touchscreens: an experimental evaluationof three strategies, Richard L. Potter, Linda J. Weldon, Ben Shneiderman
4.2 High precision touchscreens: design strategies and comparisons with a mouse, Andrew Sears, Ben Shneiderman
4.3 Touchscreens now offer compelling uses, Ben Shneiderman
4.4 Touchscreen interfaces for alphanumeric data entry, Catherine Plaisant, Andrew Sears
4.5 Scheduling home control devices: a case study of the transition from the research project to a product, Catherine Plaisant, Ben Shneiderman, Jim Battaglia
5. Public access
5.1 Guide to Opportunities in Volunteer Archaeology: case study on the use of a hypertext system , in a museum exhibit, Catherine Plaisant
5.2 Evaluating three museum installations of a hypertext system, Ben Shneiderman, Dorothy Brethauer, Catherine Plaisant, Richard Potter
5.3 ACCESS at the Library of Congress, Gary Marchionini, Maryle Ashley, Lois Korzendorfer
5.4 User interface consistency: an evaluation of original and revised interfaces for a videodisk library, Richard Chimera, Ben Shneiderman
6. Information visualization: dynamic queries, treemaps, and the filter/flow metaphor
6.1 Dynamic Queries for information exploration: an implementation and evaluation, Christopher Ahlberg, Christopher Williamson, Ben Shneiderman
6.2 The Dynamic HomeFinder: evaluating Dynamic Queries in a real-estate information exploration system, Christopher Williamson, Ben Shneiderman
6.3 Treemaps: a space-filling approach to the visualization of hierarchical information structures, Brian Johnson, Ben Shneiderman
7. Essays and explorations
7.1 A nonanthropomorphic style guide: overcoming the Humpty Dumpty syndrome, Ben Shneiderman
7.2 Human values and the future of technology: a declaration of responsibility, Ben Shneiderman
7.3 Engagement and construction: educational strategies for the post-TV era, Ben Shneiderman
7.4 Protecting rights in user interface designs, Ben Shneiderman
7.5 Declaration in Apple vs. Microsoft/Hewlett-Packard, Ben Shneiderman
Appendix-HCIL publications
Appendix-videos
Name index
Subject index


[HTML [Link to Report]

Plaisant, C. (Editor) (June 1992)
1992 Human-Computer Interaction Laboratory Video Reports
HCIL-92-17, CS-TR-3529, CAR-TR-792

Introduction - Ben Shneiderman, [3:00] Dynamic Queries: database searching by direct manipulation - Ben Shneiderman, Chris Williamson, Christopher Ahlberg, [10:55] Treemaps for visualizing hierarchical information - Ben Shneiderman, Brian Johnson, Dave Turo, [11:25] Three strategies for directory browsing - Rick Chimera, [10:30] Filter-Flow metaphor for boolean queries - Degi Young, Ben Shneiderman, [6:35] The AT&T Teaching Theater: active learning through computer supported collaborative courseware - Kent Norman, [8:25] ACCESS: an online public access catalog at the Library of Congress - Gary Marchionini, [8:15] Remote Direct Manipulation: a telepathology workstation - Catherine Plaisant, Dave Carr, [7:30] Guiding automation with pixels: a technique for programming in the user interface - Richard Potter, [11:50]


[HTML] [Link to Report]

Plaisant, C., Carr, D., Hasegawa, H. (Oct. 1992)
When an intermediate view matters: A 2D browser experiment
HCIL-92-13, CS-TR-2980, CAR-TR-645, SRC-TR-92-119.

The browsing of two dimensional images can be found in a large number of applications. When the image to be viewed is much larger than the screen available, a two dimensional browser has to be provided to allow users to access all parts of the image. We show the diversity of tasks and systems available and the need for 2D browser design guidelines. In the context of a microscope image browser, we investigate one common technique consisting of a global view of the whole image, coupled to a detailed, mag nified view of part of the image. In particular we look at the benefits of providing an intermediate view when the detail-to-overview ratio is high. An experiment showed that users performance significantly degrades when no intermediate view is provided for a detail-to-overview ratio over 20:1. Our experience is also a good example of a real world application for which added features and added hardware need to be justified.


[HTML] [Link to Report]

Plaisant, C. (May 1992)
Touchscreen toggle design
Video in CHI `92 Video Program (Monterey, CA, May 3-7, 1992) Available through ACM SIGGRAPH Video Review, issue 77, ACM, New York. A two page video summary appears in CHI' 92 Proceedings, 667-668. Video also available through HCIL as part of the 1991 HCIL Video Report. Also available on YouTube.
HCIL-92-12


[Video] [Link to Report]

Carr, D., Hasegawa, H., Lemmon, D., Plaisant, C. (March 1992)
The effects of time delays on a telepathology user interface
Proc. of the 16th Annual Symposium on Computer Applications in Medical Care , SCAMC (Baltimore, MD, Nov. 7-11, 1992) 256-260.
HCIL-92-05, CS-TR-2874, CAR-TR-616, SRC-TR-92-49.

Telepathology enables a pathologist to examine physically distant tissue samples by microscope operation over a communication link. Communication links can impose time delays which cause difficulties in controlling the remote device. Such difficulties were found in a microscope teleoperation system. Since the user interface is critical to pathologist's acceptance of telepathology, we redesigned the user interface for this system, built two different versions (a keypad whose movement commands operated by specifying a start command followed by a stop command and a trackball interface whose movement commands were incremental and directly proportional to the rotation of the trackball). We then conducted a pilot study to determine the effect of time dela ys on the new user interfaces. In our experiment, the keypad was the faster interface when the time delay is short. There was no evidence to favor either the keypad or trackball when the time delay was longer. Moving long distances over the microscope slide by dragging the field-of-view indicator on the touchscreen control panel improved inexperience user performance. Also, the experiment suggests that changes could be made to improve the trackball interface.


[Link to Report]

Plaisant, C. (Editor) (June 1991)
1991 Human-Computer Interaction Laboratory Video Reports
HCIL-91-16, CS-TR-3528, CAR-TR-791

Introduction - Ben Shneiderman, Scheduling home control devices - Catherine Plaisant, Ben Shneiderman, Touchscreen toggles - Catherine Plaisant, A home automation system - Reuel Launey (Custom Command Systems), PlayPen II (now known as PenPlay II): A novel fingerpainting program - Andrew Sears, Ben Shneiderman, Touchscreen keyboards - Andrew Sears, Ben Shneiderman, Pie menus - Don Hopkins, Three interfaces for browsing tables of contents - Rick Chimera


[HTML] [Link to Report]

Plaisant, C., Sears, A. (Sept. 1991)
Touchscreen interfaces for alphanumeric data entry
Proc. of the Human Factors Society - 36th Annual Meeting, vol. 1, (Atlanta, GA, Oct. 12-16, 1992) 293-297. Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 195-204. Also Human Factors Perspectiv es on Human-Computer Interaction, Selections from Proc. of Human Factors and Ergonomics Society Annual Meetings 1983-1994, Perlman, G., Green, G.K., Wogalter, M.S., Eds. (1995) 261-265.
HCIL-91-12, CS-TR-2764, CAR-TR-585

In cases when only limited alphanumeric data must be entered, or when layout, labeling, or size may be changed, traditional keyboards may not be optimal. A series of experiments has demonstrated the usability of touchscreen keyboards. We give a summary of the existing data concerning the usability of touchscreen keyboards including typing rates for experts and novices on keyboards of various sizes. We also report on a recent study done with representative users. Results indicate that typing rates inc rease rapidly reaching peak performance after only 25 minutes of use. Practical suggestions for the design of such a keyboard are also presented.


[Link to Report]

Keil-Slawik, R., Plaisant, C., Shneiderman, B. (April 1991)
Remote direct manipulation: A case study of a telemedicine workstation
Human Aspects in Computing: Design and Use of Interactive Systems and Information Management, 4th Int. Conf. on HCI (Stuttgart, Sept. 91) 1006-1011. Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 51-61.
HCIL-91-05, CS-TR-2655, CAR-TR-551

This paper describes our experience with the design of a remote pathologist`s workstation. We illustrate how our effort to apply direct manipulation principles led us to explore remote direct manipulation designs. The use of computer and communication systems to operate devices remotely introduces new challenges for users and designers. In addition to the usual concerns, the activation delays, reduced feedback, and increased potential for breakdowns mean that designers must be especially careful and c reative. The user interface design is closely linked to the total system design.


[Link to Report]

Plaisant, C., Shneiderman, B., Battaglia, J. (1990)
Scheduling home-control devices: a case study of the transition from the research project to a product
Human Factors in Practice, Computer Systems Technical Group, Human Factors Society (Santa Monica, CA, Dec. 1990) 7-13. Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 205-215.
HCIL-90-10

This case study describes the transition from a research project on scheduling home-control devices to a product integrated in an existing home automation system. First we describe the research that explored several designs to schedule devices over time periods ranging from minutes to days: four designs were compared, three of them prototyped and tested. One of the designs was selected for implementation in the commercial system. We then categorize the actions that were taken in order to improve and mold the prototype design into an integrated product. Finally we report on an additional study that emerged from the first one - the scheduling of periodic events - and on the extensions of the scheduler interface design to other aspects of home automat ion.


  [Link to Report]

Plaisant, C. (Nov. 1990)
Guide to opportunities in volunteer archaeology - case study of the use of a hypertext system in a museum exhibit
Hypertext/Hypermedia Handbook, Berk E. & Devlin, J., Eds., McGraw-Hill (1991) 498-505. Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 223-229.
HCIL-90-09, CS-TR-2559, CAR-TR-523

This case study shows how a hypertext system was used in a traveling exhibit of the Smithsonian Institution. The database about archaeology was constructed by a professor and students of the history department of the University of Maryland. Regular upd ates of the database were made for each new venue of the exhibit. Finally the database was translated into French and automatically rebuilt to be used in Canada. Helpful features of the hypertext system as well as the difficulties encountered are describ ed. System users were observed in the museum and collected usage data was analyzed.


[Link to Report]

Plaisant, C., Wallace, D. (Nov. 1990)
Touchscreen toggle switches: push or slide? Design issues and usability study
HCIL-90-08, CS-TR-2557, CAR-TR-521

This article describes six different touchscreen based toggle switches allowing the control of two state (ON/OFF) devices. The user interfaces, ranging from button type toggles to sliding toggles are described and compared. A usability test with 15 subjects was conducted. Error rates, user preferences and subjective satisfaction ratings were collected. Results indicate that all the toggles described here can be used with low error rates. The sliding toggles were rated harder to use and were least preferred. Individual differences in personal preference were shown to be very large. It was also observed that users spontaneously or after one trial use a sliding motion to activate a control showing a sliding affordance.


[Video] [Link to Report]

Shneiderman, B., Plaisant, C., Botafogo, R., Hopkins, D., Weiland, W. (revised May 1991)
Designing to facilitate browsing: a look back at the Hyperties work station browser
Hypermedia, vol. 3, 2 (1991)101-117. Based on Visual engagement and low cognitive load in browsing hypertext.
HCIL-90-02, CS-TR-2433, CAR-TR-494

This paper reviews our designs to facilitate browsing that were developed, implemented, and tested in the SUN version of Hyperties: (1) A markup language for generating highly legible documents on a large high resolution display, including legible fonts and appropriate layout. (2) Innovative solutions to link identification and selection including pop-out graphical buttons of arbitrary shape. (3) Low cognitive load operations to avoid distraction of common operations such as page turning or window selec tion. (4) We implemented several multiple window selection strategies and conducted empirical tests. We preferred piles-of-tiles, in which standard-sized windows were arranged in a consistent pattern on the display and operations could be done rapidly a nd easily so as to minimize distraction from the contents.


[Link to Report]

Sears, A., Plaisant, C., Shneiderman, B. (June 1990)
A new era for high-precision touchscreens
Advances in Human-Computer Interaction, vol. 3, Hartson, R. & Hix, D. Eds., Ablex (1992) 1-33.
HCIL-90-01, CS-TR-2487, CAR-TR-506

While many input devices allow interfaces to be customized, increased directness distinguishes touchscreens. Touchscreens are easy to learn to use, fast, and result in low error rates when interfaces are designed carefully. Many actions which are diffi cult with a mouse, joystick, or keyboard are simple when using a touchscreen. Making rapid selections at widely separated locations on the screen, signing your name, dragging the hands of a clock in a circular motion are all simple when using a touchscre en, but may be awkward using other devices. This paper presents recent empirical research which can provide a basis for theories of touchscreen usage. We believe recent improvements warrant increased use of touchscreens.


[Link to Report]

Furuta, R., Plaisant, C., Shneiderman, B. (Dec. 1989)
Automatically transforming regularly structured linear documents into hypertext
Electronic Publishing - Origination, Dissemination and Design, vol. 2, 4 (1990) 211-229.
HCIL-89-20

Fully automatic conversion of a paper-based document into hypertext can be achieved in many cases if the original document is naturally partitioned into a collection of small-sized pieces that are unambiguously and consistently structured. We describe t he methodology that we have used successfully to design and implement several straightforward conversions from the original document's machine-readable markup.


[Link to Report]

Plaisant, C., Shneiderman, B. (revised Feb. 1991)
Scheduling home control devices: design issues and usability evaluation of four touchscreen interfaces
International Journal of Man-Machine Studies (1992) 36, 375-393.
HCIL-89-18, CS-TR-2352, CAR-TR-472

This article describes four different user interfaces supporting scheduling two-state (ON/OFF) devices over time periods ranging from minutes to days. The touchscreen-based user interfaces including a digital, 12-h clock, 24-h linear and 24-h dial proto types are described and compared on a feature by feature basis. A formative usability test with 14 subjects, feedback from more than 30 reviewers, and the flexibility to add functions favour the 24-h linear version.


[Video] [Link to Report]

Faloustos, C., Lee, R., Plaisant, C., Shneiderman, B. (June 1989)
Incorporating string search in a hypertext system: user interface and signature file design issues
Hypermedia, vol. 2, 3 (1991).
HCIL-89-16, CS-TR-2266, CAR-TR-448

Hypertext systems provide an appealing mechanism for informally browsing databases by traversing selectable links. However, in many fact finding sirtuations string search is an effective complement to browsing. This paper describes the application of t he signature file method to achieve rapid and convenient string search in a hypertext environment. The method has been implemented in a prototype, as well as in a commercial product. Performance data for search times and storage space are presented from a commercial hypertext database. User interface issues are then discussed.


[Link to Report]

Furuta, R., Plaisant, C., Shneiderman, B. (May 1989)
A spectrum of automatic hypertext constructions
Hypermedia, vol. 1, 2 (1989) 179-195.
HCIL-89-15, CS-TR-2253, CAR-TR-443

We describe our experiences with four separate conversions from paper documents into hypertext and discuss the lessons we have learned. The paper document's organization affects the ease with which it can be converted and the appropriateness of the resu lting hypertext. The form of the paper document's machine-readable `markup' description affects the ability to transform the structure automatically. Designing the link structures that tie together the parts of the hypertext takes special care in automa ting, as badly-designed and incorrectly-formed links destroy the integrity of the hypertext. Overall, each of the conversions followed the same basic methodology, providing the handle for the development of `power tools' that can be applied to simplify s ubsequent conversions.


[Link to Report]

Plaisant, C. (May 1989)
Semi-automatic conversion to a hypertext database, the case study of the NCR management college course catalog
HCIL-89-14

The case study of the NCR management college course catalog. This document describes the different phases of the process of automatically converting a large set of documents to a Hyperties database. For each of those phases, we give details about the importation of our example database and describe the tools used . We discuss the problems encountered and try to generalize our study to other cases.


 [Link to Report]

Shneiderman, B., Brethauer, D., Plaisant, C., Potter, R. (May 1989)
Evaluating three museum installations of a hypertext
Journal of the American Society for Information Science, 40(3) 172-182. Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 231-250.
HCIL-89-08

This study explores the use of a hypertext system by patrons of three museums. Data on the articles accessed, the time spent in each, the number of times the index was accessed, etc. were collected from a total of more than 5000 sessions. Results show that visitors at all three museums used the embedded menus of the Hyperties hypertext system in moving from one article to another far more than the traditional index. Article selection appears to reflect anticipated interests of patrons at each museum s uggesting success in traversing the database. At the third museum, the data collection was complemented by direct observation and interviews of the museum patrons. This approach appears to be more appropriate to analyze the usage data as well as to imp rove the user interface and database structure.


 [Link to Report]

Wallace, D., Norman, K., Plaisant, C. (Sept. 1988)
The american voice and robotics "guardian" system: a case study in user interface usability evaluation
HCIL-88-10, CS-TR-2113, CAR-TR-392

American Voice and Robotics (AVR), in conjunction with the Maryland Industrial Partnerships (MIPS) program, contracted the Human-Computer Interaction Laboratory (HCIL) to evaluate the user interface of AVR's "Guardian" home automation system. Among their goals for the system were: Ease of use and learning of the system (intuitiveness). Aesthetic appeal, Unintimidating, Impressive, High Functionality, Fast and accurate input of user action, Clear feedback, Forgiving to errors, and Fun to use. Researchers found that users were initially impressed with the system, but that they were not fully satisfied with it. Specific initial recommendations, theoretical and methodological concerns, procedures, results, and direction of future research will be discussed.


[Link to Report]


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