We present Redgraph, the first generic virtual reality visualization program for Semantic Web data. Redgraph is capable of handling large data-sets, which we demonstrate on social network data from the U.S. Patent Trade Office. We develop a Semantic Web vocabulary of virtual reality terms compatible with GraphXML to map graph visualization into the Semantic Web itself. Our approach in visualizing Semantic Web data takes advantage of user-interaction in an immersive environment to bypass a number of difficult issues in the 3-dimensional graph visualization layout problem by relying on the user themselves to interactively extrude the nodes and links of a 2-dimensional network into the third dimension. When users touch nodes in the virtual reality environment, they retrieve data formatted according to the data's schema or ontology. We applied Redgraph to social network data constructed from patents, inventors, and institutions from the United States Patent and Trademark Office in order to explore networks of innovation in computing. Using this data-set, we present the results of a user study comparing extrusion (3-D) vs. no-extrusion (2-D). The use of a 3-D interface showed that subjects led to significant improvement on answering of fine-grained questions about the data-set, but no significant difference was found broad questions about the overall structure of the data were asked. Furthermore, inference can be used to improve the visualization, as demonstrated with a data-set of biotechnology patents and researchers.


Downloads:

Download	Description	Dependencies	Tested
redgraph.mov	We filmed a video, demonstrating the application during the 2007 HASTAC conference
core.n3	the patent data used for demos and the userstudy
redgraph 3d v0.21	mainly work from Fall 2007-Spring 2008. now cross platform (win32/linux). Boost for initial layout. Moved to Custom N-triples parser due to lack of Redland (librdf) support for win32. support for loading/saving of positions. reading of schema for human readable data field titles. has java gui to trigger loading/saving. 0.2 to 0.21 added bug fix for text display and also update of layout functions (to work with latest boost).	Syzygy boost	Ubuntu 10.04 (gcc 4.4.3) Mingw (gcc 3.4.5) Mingw TDM (gcc 4.4.1)
redgraph 2d v0.1	special 2d version of redgraph. developed for the RENCI multitouch wall. cross platform.	oscpack boost glut (win32)	Ubuntu 10.04 (gcc 4.4.3) Mingw (gcc 3.4.5) Mingw TDM (gcc 4.4.1)