Interactive visualization of heterogeneous social networks using glyphs

There is a growing need for visualizing heterogeneous social networks as new data sets become available. However, the existing visualization tools do not address the challenge of reading topological information introduced by heterogeneous node and link types. To resolve this issue, we introduce glyphs to node-link diagrams to conveniently represent the multivariate nature of heterogeneous node and link types. This provides the opportunity to visually reorganize topological information of the heterogeneous social networks without losing connectivity information. Moreover, a set of interaction techniques are provided to the analyst to give total control over the reorganization process. Finally, a case study is presented to using InfoVis 2008 data set to show the exploration process

Solving challenging grid puzzles with answer set programming

We study four challenging grid puzzles, Nurikabe, Heyawake, Masyu, Bag Puzzle, interesting for answer set programming (ASP) from the viewpoints of representation and computation: they show expressivity of ASP, they are good examples of a representation methodology, and they form a useful suite of benchmarks for evaluating/improving computational methods for nontight programs

Commentary: Cornfield on cigarette smoking and lung cancer and how to assess causality

This paper presents some of the findings of an ongoing study conducted by an interdisciplinary team of computer scientists, artists and designers. It concerns the development of 3D user interfaces that aid the navigation and representation of large data structures through the usage of the HSV color space, and the ensuing “spatial frames”. While data objects that have been colorized in various hues that carry equal saturation and brightness/transparency value seem to be equally foregrounded; varying saturation, brightness and transparency values add depth and hierarchy: Less saturated and/or darker, more transparent values recede into the background, while brighter, more highly saturated objects tend to become foregrounded. During our experiments we noticed that, when thus colorized, the edges connecting the nodes form visual spatial frames, which can result in the meaningful partitioning of 3D space. This property can be exploited to facilitate the display of overall trends within data sets, as well as to ease navigation, presenting overviews of the structure, and navigational help

GlyphLink: an interactive visualization approach for semantic graphs

Graph analysis by data visualization involves achieving a series of topology-based tasks. When the graph data belongs to a data domain that contains multiple node and link types, as in the case of semantic graphs, topology-based tasks become more challenging. To reduce visual complexity in semantic graphs, we propose an approach which is based on applying relational operations such as selecting and joining nodes of different types. We use node aggregation to reflect the relational operations to the graph. We introduce glyphs for representing aggregated nodes. Using glyphs lets us encode connectivity information of multiple nodes with a single glyph. We also use visual parameters of the glyph to encode node attributes or type specific information. Rather than doing the operations in the data abstraction layer and presenting the user with the resulting visualization, we propose an interactive approach where the user can iteratively apply the relational operations directly on the visualization. We present the efficiency of our method by the results of a usability study that includes a case study on a subset of the International Movie Database. The results of the controlled experiment in our usability study indicate a statistically significant contribution in reducing the completion time of the evaluation tasks