Abstract This paper reports on the development and assessment of the EarthSystemsVisualizer (ESV), a geovisualization tool designed to facilitate learning about global weather. Our goals in designing ESV were to evaluate two exploratory spatial data analysis (ESDA) techniques, temporal brushing and temporal focusing,and to determine whether interactive geovisualization tools influence problem solving strategies, approaches to learning, and students' ability to generate hypotheses about earth-science processes. Focus group sessions were conducted with both expert and novice users to assess an initial design for the ESV interface prior to conducting a task-based assessment of ESV use. Changes were implemented in response to the focus group results, including the redesign of a temporal legend and improved speed and direction controls. Our task-based assessment considered student reactions to components of ESV, especially whether they could use it to answer questions about global-scale weather processes, and whether the system (particularly its focusing and brushing tools) had an impact on the hypotheses generated about relationships among weather variables. The assessment revealed that focusing and brushing had little impact on students' ability to answer questions about weather processes, and that performance suffered for students who were confused by the focusing and brushing tools. In fact, students who understood the tools performed the best, but students without the tools performed better than those who had the tools but were unsure how to use them. We also concluded that the level of the visualization system must be well matched to the knowledge users have about the application domain: students who already possessed an advanced understanding of meteorology or climatology benefited less and were more critical of the system than students with an intermediate or a novice level of understanding.
Understanding the spatial and temporal characteristics of individual and group behavior in social networks is a critical component of visual tools for intelligence analysis, emergency management, consumer analysis, and human geography. Identification and analysis of patterns of recurring events is an essential feature of such tools. In this paper, we describe an interactive visual tool for exploring the visitation patterns of guests at two hotels in central Pennsylvania from 1894 to 1900. The centerpiece of the tool is a wrapping spreadsheet technique, called reruns, that reveals regular and irregular periodic patterns of events in multiple overlapping artificial and natural calendars. Implemented as a coordinated multiple view visualization in Improvise, the tool is in ongoing development through an iterative process of data collection, transcription, hypothesis, design, discovery, analysis, and evaluation in close collaboration with historical geographers. Numerous discoveries have driven additional data collection from archival newspaper and census sources, as well as plans to enhance analysis of spatial patterns using historic weather records and railroad schedules. Distributed online evaluations of usability and usefulness have resulted in feature and design recommendations that are being incorporated into the tool.
MapStats for Kids is concerned with the development of online learning activities based on data from the FedStats web portal. The development of these web applications requires that the tools will be useful and usable for students, grades 4-8. In order to assess web applications developed according to the above requirements a range of usability testing methods are being applied within the project.
The volume of health science publications is escalating rapidly. Thus, keeping up with developments is becoming harder as is the task of finding important cross-domain connections. When geographic location is a relevant component of research reported in publications, these tasks are more difficult because standard search and indexing facilities have limited or no ability to identify geographic foci in documents. This paper introduces HEALTH GeoJunction, a web application that supports researchers in the task of quickly finding scientific publications that are relevant geographically and temporally as well as thematically. HEALTH GeoJunction is a geovisual analytics-enabled web application providing: (a) web services using computational reasoning methods to extract place-time-concept information from bibliographic data for documents and (b) visually-enabled place-time-concept query, filtering, and contextualizing tools that apply to both the documents and their extracted content. This paper focuses specifically on strategies for visually-enabled, iterative, facet-like, place-time-concept filtering that allows analysts to quickly drill down to scientific findings of interest in PubMed abstracts and to explore relations among abstracts and extracted concepts in place and time. The approach enables analysts to: find publications without knowing all relevant query parameters, recognize unanticipated geographic relations within and among documents in multiple health domains, identify the thematic emphasis of research targeting particular places, notice changes in concepts over time, and notice changes in places where concepts are emphasized. PubMed is a database of over 19 million biomedical abstracts and citations maintained by the National Center for Biotechnology Information; achieving quick filtering is an important contribution due to the database size. Including geography in filters is important due to rapidly escalating attention to geographic factors in public health. The implementation of mechanisms for iterative place-time-concept filtering makes it possible to narrow searches efficiently and quickly from thousands of documents to a small subset that meet place-time-concept constraints. Support for a more-like-this query creates the potential to identify unexpected connections across diverse areas of research. Multi-view visualization methods support understanding of the place, time, and concept components of document collections and enable comparison of filtered query results to the full set of publications.
This dissertation reports the results of an empirical study designed to examine how experts use maps in conjunction with other statistical graphics to think about the problem of Hantavirus Pulmonary Syndrome (HPS) risk. 18 scientists from one of three disciplines (ecology, epidemiology and geography) were asked to use a geographical simulation model to explore the case study problem. They were able to interact with the data and the model through three forms of visual display: maps, scatterplots and time series graphs. To provide a complete picture of users' interaction with the model, data was collected on what participants saw, did and thought while using the model by videorecording participants while they were thinking aloud. The transcribed data were coded with categories designed to provide evidence to address four core research questions: (1) What do participants do with the system? (2) What kinds of information do users attend to in the visual information display? (3) How is the information obtained from the system used? (4) What kinds of hypotheses are generated?
Users manipulated maps more often than scatterplots and scatterplots more often than time series graphs. User patterns of visual attention were similar to their patterns of system manipulation. Maps were attended to most commonly when users made comparisons over time, and scatterplots were attended to most commonly when users made comparisons over attributes. The characteristics of the hypotheses a user generated were related to the visual information display type the user attended to. The patterns of attention to tools, tool use and hypothesis characteristics that differed between scientists from different disciplines were related to users' strategies for model exploration. The role of (domain knowledge-based) expertise on tool use is an indirect one: rather than a person's expertise directly influencing his or her choice of tools, this expertise influences his or her choice of exploration strategy, and thereby, choice of tools. This finding provides us with a first step in understanding how users' strategies guide their choice of tools and how the ways in which working with these tools have an impact on how users approach a modeling problem.