Lifelines2: Interactive Visualization of Temporal Categorical Data

2:00pm, February 17, Tuesday, 2009, ST2, 430 (Notice the time change)

Speaker

Taowei David Wang
Ph.D candidate
Department of Computer Science
University of Maryland, College Park

Abstract

As large data repositories of temporal data become more prevalent today, it also becomes more important to develop appropriate techniques to support visual exploratory tasks on this type of data. Although much work has been done to develop techniques for numerical time series, temporal categorical data has been mostly overlooked. This type of data is best characterized by events that have names and time stamps. To be able to study the ordering of events and the prevalence of ordering can reveal interesting relationships among the different events, and consequently help analysts formulate new hypotheses, gain new insights. I present Lifelines2, an interactive visualization system designed for visual analysis of temporal categorical data across multiple records.

At the center of Lifelines2 is the Align-Rank-Filter (ARF) framework. It allows users to quickly manipulate how they see the data by their features. Alignment lets users specify a reference event, and subsequently change the view of data to be relative to that event. This facilitates the discovery of important temporal relationships associated with the reference events. Rank and Filter are old ideas that let users reorder and trim the data. Coupled with alignment, however, they also offer new affordances to support more sophisticated exploratory tasks.

In this talk, I present the features of Lifelines2, and show a video on how a medical researcher might use Lifelines2 to identify patients who exhibit a certain pattern of medical events. I will also present the results from our controlled study, which shows that the alignment feature is instrumental in aiding users to perform complex tasks. Finally, I will talk about the first impressions of Lifelines2 from our collaborators, and peek at our future research on the topic.

Short Bio

Taowei David Wang is a Ph.D candidate in the Department of Computer Science in the University of Maryland. He is part of the Human Computer Interaction Lab, and is advised by Ben Shneiderman. His dissertation topic is on interactive visualization techniques of temporal categorical data for the purpose of hypothesis generation. He is currently working closely with physicians and clinicians on searches over electronic health records for this purpose, and is scheduled to graduate in the winter of 2009.

Talk Slides