1. Graph Visualization cs5764: Information Visualization Chris North

2. Where are we? Multi-D 1D 2D 3D Trees Graphs Document collections Design Principles Empirical Evaluation Visual Overviews

3. Networks Graph = nodes + edges Nodes and edges have attributes Tabular storage: 1 table for nodes, 1 table for edges Examples: Web, roads, telephone, internet, cpu architecture, travel, document citations Tasks: shortest path, all paths neighbors, degree topology, connected components, sub-graphs Web domain: broken links, navigation, update, sitemap, orientation

4. Visualization Approaches Connections (nodes & links) Nodes: –Size, color, shape, location, label, … Links: –Direction, width, color, shape, label, … Other approaches? adjacency matrix, containment, … A C B A

6. Yuk

7. Challenges Graph layout Scale Navigation Problem: Bowl of spaghetti!

8. Graph Layout Styles Straight line Arc Orthogonal

9. Aesthetic constraints Minimize link crossings Minimize link lengths Minimize link bends Maximize symmetries …

10. Not Trivial

11. Common Layout Algorithms Circular Concentric Layering Force directed Clustering Hierarchical clustering Convert to tree Geographic, pre-determined

12. Circular Layout

13. Radial Layout http://bailando.sims.berkeley.edu/infovis.html

14. Force directed layout Springs, gravity, clustering http://java.sun.com/applets/jdk/1.2/demo/applets/GraphLayout/example1.html

15. Tree Layout WebSphinx http://www-2.cs.cmu.edu/~rcm/websphinx/workbench.html

16. Hyperbolic Layout Munzner, “H3”

17. Attribute Value Layout Eick, “SeeNet”

18. Scale up

19. Multi-Digraphs Korn, “Multi-Digraphs”

20. Adjacency Matrix Connex by PNNL

21. Hierarchical Aggregation by Feiner 1. Cluster

22. 2. Group hierarchically Hierarchical Aggregation

23. 3. Link inheritance

24. SHriMP Storey, “SHriMP”

25. ThinkMap – Visual Thesaurus http://www.visualthesaurus.com Show only depth 1 from focus node

26. Harmony Web Browser by Keith Andrews Show limited depth from focus node

27. Harmony Web Landscape 3D

29. StarLight http://www.pnl.gov/infoviz/technologies.html#starlight PNL