-
[show abstract]
[hide abstract]
ABSTRACT: Visualizations of static networks in the form of node-link diagrams have evolved rapidly, though researchers are still grappling with how best to show evolution of nodes over time in these diagrams. This paper introduces NetVisia, a social network visualization system designed to support users in exploring temporal evolution in networks by using heat maps to display node attribute changes over time. NetVisia's novel contributions to network visualizations are to (1) cluster nodes in the heat map by similar metric values instead of by topological similarity, and (2) align nodes in the heat map by events. We compare NetVisia to existing systems and describe a formative user evaluation of a NetVisia prototype with four participants that emphasized the need for tooltips and coordinated views. Despite the presence of some usability issues, in 30-40 minutes the user evaluation participants discovered new insights about the data set which had not been discovered using other systems. We discuss implemented improvements to NetVisia, and analyze a co-occurrence network of 228 business intelligence concepts and entities. This analysis confirms the utility of a clustered heat map to discover outlier nodes and time periods.
SocialCom '11: Proc. 2011 IEEE 3rd International Conference on Social Computing; 01/2011
-
[show abstract]
[hide abstract]
ABSTRACT: Keeping up with rapidly growing research fields, especially when there are multiple interdisciplinary sources, requires substantial effort for researchers, program managers, or venture capital investors. Current theories and tools are directed at finding a paper or website, not gaining an understanding of the key papers, authors, controversies, and hypotheses. This report presents an effort to integrate statistics, text analysis, and visualization in a multiple coordinated window environment that supports exploration. Our prototype system, Action Science Explorer (ASE), provides an environment for demonstrating principles of coordination and conducting iterative usability tests of them with interested and knowledgeable users. We developed an understanding of the value of reference management, statistics, citation context extraction, natural language summarization for single and multiple documents, filters to interactively select key papers, and network visualization to see citation patterns and identify clusters. The three-phase usability study guided our revisions to ASE and led us to improve the testing methods.
01/2011;
-
[show abstract]
[hide abstract]
ABSTRACT: Action Science Explorer (ASE) is a tool designed to support users in rapidly generating readily consumable summaries of academic literature. It uses citation network visualization, ranking and filtering papers by network statistics, and automatic clustering and summarization techniques. We describe how early formative evaluations of ASE led to a mature system evaluation, consisting of an in-depth empirical evaluation with four domain experts. The evaluation tasks were of two types: predefined tasks to test system performance in common scenarios, and user-defined tasks to test the system's usefulness for custom exploration goals. The primary contribution of this paper is a validation of the ASE design and recommendations to provide: easy-to-understand metrics for ranking and filtering documents, user control over which document sets to explore, and overviews of the document set in coordinated views along with details-on-demand of specific papers. We contribute a taxonomy of features for literature search and exploration tools and describe exploration goals identified by our participants.
VL/HCC '11: Proc. 2011 IEEE Symposium on Visual Languages and Human-Centric Computing; 01/2011
-
[show abstract]
[hide abstract]
ABSTRACT: This paper reviews the trajectory of three information visualization innovations: treemaps, cone trees, and hyperbolic trees. These three ideas were first published around the same time in the early 1990s, so we are able to track academic publications, patents, and trade press articles over almost two decades. We describe the early history of each approach, problems with data collection from differing sources, appropriate metrics, and strategies for visualizing these longitudinal data sets. This paper makes two contributions: (1) it offers the information visualization community a history of how certain ideas evolved, influenced others, and were adopted for widespread use and (2) it provides an example of how such scientometric trajectories of innovations can be gathered and visualized. Guidance for designers is offered, but these conjectures may also be useful to researchers, research managers, science policy analysts, and venture capitalists.
Information Visualization. 01/2011;
-
PASSAT/SocialCom 2011, Privacy, Security, Risk and Trust (PASSAT), 2011 IEEE Third International Conference on and 2011 IEEE Third International Confernece on Social Computing (SocialCom), Boston, MA, USA, 9-11 Oct., 2011; 01/2011
-
Social Computing, Behavioral-Cultural Modeling and Prediction - 4th International Conference, SBP 2011, College Park, MD, USA, March 29-31, 2011. Proceedings; 01/2011
-
Social Computing, Behavioral-Cultural Modeling and Prediction - 4th International Conference, SBP 2011, College Park, MD, USA, March 29-31, 2011. Proceedings; 01/2011
-
[show abstract]
[hide abstract]
ABSTRACT: EventGraphs are social media network diagrams of conversations related to events, such as conferences. Many conferences now communicate a common "hashtag" or keyword to identify messages related to the event. EventGraphs help make sense of the collections of connections that form when people follow, reply or mention one another and a keyword. This paper defines EventGraphs, characterizes different types, and shows how the social media network analysis add-in NodeXL supports their creation and analysis. The structural patterns to look for in EventGraphs are highlighted and design ideas for their improvement are discussed.
44th Hawaii International International Conference on Systems Science (HICSS-44 2011), Proceedings, 4-7 January 2011, Koloa, Kauai, HI, USA; 01/2011
-
Active Media Technology, 6th International Conference, AMT 2010, Toronto, Canada, August 28-30, 2010. Proceedings; 01/2010
-
[show abstract]
[hide abstract]
ABSTRACT: Designing graph drawings that effectively communicate the underlying network is challenging as for every network there are many potential unintelligible or even misleading drawings. Automated graph layout algorithms have helped, but frequently generate ineffective drawings. In order to build awareness of effective graph drawing strategies, we detail textitreadability metrics on a [0,1] continuous scale for textitnode occlusion, textitedge crossing, textitedge crossing angle, and textitedge tunneling and summarize many more. Additionally, we define new textitnode & edge readability metrics to provide more localized identification of where improvement is needed. These are implemented in SocialAction, a tool for social network analysis, in order to direct users towards poor areas of the drawing and provide real-time readability metric feedback as users manipulate it. These contributions are aimed at heightening the awareness of network analysts that the images they share or publish could be of higher quality, so that readers could extract relevant information.
05/2009;
-
[show abstract]
[hide abstract]
ABSTRACT: Social Network Analysis (SNA) has evolved as a popular, standard method for modeling meaningful, often hidden structural relationships in communities. Existing SNA tools often involve extensive pre-processing or intensive programming skills that can challenge practitioners and students alike. NodeXL, an open-source template for Microsoft Excel, integrates a library of common network metrics and graph layout algorithms within the familiar spreadsheet format, offering a potentially low-barrier-to-entry framework for teaching and learning SNA. We present the preliminary findings of 2 user studies of 21 graduate students who engaged in SNA using NodeXL. The majority of students, while information professionals, had little technical background or experience with SNA techniques. Six of the participants had more technical backgrounds and were chosen specifically for their experience with graph drawing and information visualization. Our primary objectives were (1) to evaluate NodeXL as an SNA tool for a broad base of users and (2) to explore methods for teaching SNA. Our complementary dual case-study format demonstrates the usability of NodeXL for a diverse set of users, and significantly, the power of a tightly integrated metrics/visualization tool to spark insight and facilitate sense-making for students of SNA.
SIN '09: Proc. international symposium on Social Intelligence and Networking; 01/2009
-
Proceedings of the Fourth International Conference on Communities and Technologies, C&T 2009, University Park, PA, USA, June 25-27, 2009; 01/2009
-
[show abstract]
[hide abstract]
ABSTRACT: Effective graph drawing is challenging as every network al-lows many unintelligible or misleading drawings. To build awareness of effective graph drawing strategies, we detail quality metrics on a [0,1] continuous scale for node occlu-sion, edge crossing, edge crossing angle, and edge tunneling, summarize many more, and define new node & edge qual-ity metrics. Implemented in SocialAction, a social network analysis tool, these identify poor areas of the drawing and provide real-time feedback as users manipulate it. These contributions are aimed at heightening awareness of com-munity analysts that their images could be higher quality, so that readers could extract relevant information.
-
[show abstract]
[hide abstract]
ABSTRACT: In this paper we talk about speeding up calculation of graph metrics and layout with NodeXL by exploiting the parallel architecture of modern day Graphics Processing Units (GPU), specifically Compute Unified Device Architecture (CUDA) by Nvidia. Graph centrality metrics like Eigenvector, Betweenness, Page Rank and layout algorithms like Fruchterman-Rheingold are essential components of Social Network Analysis (SNA). With the growth in adoption of SNA in different domains and increasing availability of huge networked datasets for analysis, social network analysts are looking for tools that are faster and more scalable. Our results show up to 802 times speedup for a Fruchterman-Rheingold graph layout and up to 17,972 times speedup for Eigenvector centrality metric calculations.
-
[show abstract]
[hide abstract]
ABSTRACT: The American Recovery and Reinvestment Act dedicated $787 billion to stimulate the US economy and mandated the release of the data describing the exact distribution of that money. The dataset is a large and complex one; one of its distinguishing features is its bi-hierarchical structure, arising from the distribution of money through agencies to specific projects and the natural aggregation of awards based on location. To offer a comprehensive overview of the data, a visualization must incorporate both these hierarchies. We present TreeCovery, a tool that accomplishes this through the use of two coordinated treemaps. The tool includes a number of innovative features, including coordinated zooming and filtering and a proportional highlighting technique across the two trees. TreeCovery was designed to facilitate data exploration, and initial user studies suggest that it will be helpful in insight generation. RATB(Recovery Accountability and Transparency Board) has tested TreeCovery and considering to include the concept into their visual analytics.
-
[show abstract]
[hide abstract]
ABSTRACT: 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.
