StarWalker: A Three-dimensional Multi-user Virtual Environment before CiteSpace

11/8/2024

Among the top 7 of my most cited publications, 6 of them are related to CiteSpace. Retrospectively, the first CiteSpace paper was the 2004 PNAS paper on searching for intellectual turning points. It was followed by the 2006 paper on CiteSpace II with further developed principles and methods through two in-depth case studies. The 2006 paper has received 7,077 citations as of today (11/8/2024). In this bog, however, I will focus on what came before CiteSpace - StarWalker.

Chen C (2006) CiteSpace II: Detecting and visualizing emerging trends and transient patterns in scientific literature. Journal of the American Society for Information Science and Technology, 57 (3), 359-377. 7077

Chen C (2004) Searching for intellectual turning points: progressive knowledge domain visualization. Proceedings of the National Academy of Sciences 101 (suppl_1), 5303-5310. 2860

Börner K, Chen C, Boyack KW (2003) Visualizing knowledge domains. Annual review of information science and technology 37 (1), 179-255. 2362

Chen C, Ibekwe‐SanJuan F, Hou J (2010) The structure and dynamics of cocitation clusters: A multiple‐perspective cocitation analysis. Journal of the American Society for information Science and Technology, 61 (7), 1386-1409. 2023

Chen C (2017) Science Mapping: A Systematic Review of the Literature. Journal of Data and Information Science 2 (2), 1-40. 1847

Chen C, Hu Z, Liu S, Tseng H (2012) Emerging trends in regenerative medicine: a scientometric analysis in CiteSpace. Expert Opinion on Biological Therapy 12 (5), 593-608. 1402

Chen C, Song M (2019) Visualizing a Field of Research: A Methodology of Systematic Scientometric Reviews. PLoS One 14 (10), e0223994. 1019

Pathfinder Network Scaling

Pathfinder Network Scaling is a neat idea to handle a network with a large number of links, especially when there are too many of them to see the forest. The simplest solution to reduce the number of links in a network is the minimum spanning tree (MST). However, a network may have multiple MSTs. In other word, the solution with an MST is not unique. We may miss the most representative one in a broader context. Pathfinder, on the other hand, is complete and unique given that it is the set union of all the MSTs from the network. This is a very elegant feature. The network shown below is a Pathfinder network.

A Pathfinder network is particularly suitable to capture the backbone of the underlying network structure. Here are some examples of co-citation networks I created in late 1990s using VRML - Virtual Reality Markup Language.

Virtual Worlds

The VRML-based visualizations offers a natural 3-dimensional interactive virtual environment. The 2-dimensional base map is served by a Pathfinder network of an underlying co-citation network, whereas the 3rd dimension was used to show the citation growth of each node, i.e., a network-based 3-dimensional bar chart.

VRML models can depict the lifecycle of a publication, from its pre-publication state to its post-publication life and how fast/slow it gets citations. Of course, as we know, some publications may attract no citations for a very long time or never. VRML models allow us to play back the development of the landscape of a research field over time. An interesting and recurring pattern across several different research domains emerged. Early developments often appeared initially at the outmost branches of a Pathfinder network, for example, in areas marked as 1, 2, and 3 in the figure below. Subsequent publications tend to fill up the gaps and voids closer to the center of the network as the time went forward (for example, gaps marked as 4, 5, 6, and 7. Eventually, the central area would tend to be not only fully consolidated but also attracted the most volume of citations.

Naturally, multiple models of a variety of research domains can be organized in a spatially unlimited virtual world for users to interact with these gateways to scholarly publications through a virtual world view shown below.

Here is a snapshot of a moment of an evolving network. One tick in this model is one year passed in the real world!

StarWalker

Back to 1997-1999, VRML and multiuser virtual environments were popular. Browsers such as Netscape were VRML-friendly. Another natural step was to embed a virtual world model in a multiuser virtual environment so that multiple visitors may explore the virtual world together. Instead of relying on the gravity to hold things together in the real world, in our virtual world the idea was to attract visitors with the semantics of the underlying publications. The semantic concentrations mimic stars and galaxies in our universe, while space travelers, semantic explorers, or, as Vannevar Bush called it, trailblazers can navigate freely and pursue their interest in a virtual universe - hence the name StarWalker. I wasn't aware of anyone called SkyWalker until later at a Hypertext conference.

As you can see, some like-minded avatars gathered around some highly cited areas of publications. They can chat with each other and presumably their conversations were often inspired by publications nearby, similar to how people chat in front of a painting of common interest in a museum.

I explored this idea further in collaboration with Katy Borner (Chen & Borner 2005). We studied how users explored research literature of information visualization in a virtual world: how long did they stay in one place? How did they move in the virtual world with reference to the relevance of publications nearby?

You may find more details in references listed below.

References

Chen C (1997) Tracking latent domain structures: An integration of Pathfinder and Latent Semantic Analysis. AI & society, 11, 48-62.

Chen C, Carr L (1999) Trailblazing the literature of hypertext: author co-citation analysis (1989–1998). Proceedings of the tenth ACM Conference on Hypertext and hypermedia: returning to our diverse roots: returning to our diverse roots. pp. 51-60.

Chen C (1999) The StarWalker virtual environment-an integrative design for social navigation. Proceedings of the HCI International'99 (the 8th International Conference on Human-Computer Interaction) on Human-Computer Interaction: Communication, Cooperation, and Application Design, Volume 2, pp. 207-211.

Chen C (2004) Information Visualization: Beyond the Horizon. Springer.

Chen C, K Börner K (2005) From spatial proximity to semantic coherence: A quantitative approach to the study of group dynamics in collaborative virtual environments. Presence, 14 (1), 81-103.