A Comparison of the Readability of Graphs Using Node-Link and Matrix-Based Representations

Introduction to Graph VisualizationPage 1

Node-link diagrams are the traditional standard for graph visualization but suffer from occlusion and link-crossing issues as graphs grow in size and density. Matrix-based representations offer a clutter-free alternative, though they are less intuitive to users.

Experimental MethodologyPage 2

The study evaluated seven generic tasks on random graphs of varying sizes (20, 50, 100 vertices) and densities (0.2, 0.4, 0.6). The tasks included node/edge counting, finding specific nodes, identifying connections, and path finding. Researchers measured user accuracy and execution time.

Comparison ResultsPage 3

Results show that node-link diagrams are effective for small graphs but deteriorate rapidly as size and density increase. Matrix-based representations perform significantly better on tasks like node counting, most-connected node identification, and link finding for larger or denser graphs.

Conclusions and RecommendationsPage 4

Node-link diagrams remain the default preference for small graphs. However, for larger or dense graphs, matrix-based representations are superior in readability and accuracy. Path-finding remains challenging on both, often requiring interactive enhancements regardless of the chosen representation.