Visualizing Extensions of Argumentation Frameworks as Layered Graphs
This work addresses the need for better visualization tools in argumentation frameworks to aid users in exploring AFs, understanding extensions, and verifying algorithms, though it is incremental as it builds on existing graphical representations.
The paper tackles the problem of visualizing argumentation frameworks (AFs) and their extensions by introducing a new 3-layer graph layout technique, which reduces edge crossings through an exact ILP-based approach and a fast heuristic that produces at most twice as many crossings as optimal in most cases.
The visualization of argumentation frameworks (AFs) is crucial for enabling a wide applicability of argumentative tools. However, their visualization is often considered only as an accompanying part of tools for computing semantics and standard graphical representations are used. We introduce a new visualization technique that draws an AF, together with an extension (as part of the input), as a 3-layer graph layout. Our technique supports the user to more easily explore the visualized AF, better understand extensions, and verify algorithms for computing semantics. To optimize the visual clarity and aesthetics of this layout, we propose to minimize edge crossings in our 3-layer drawing. We do so by an exact ILP-based approach, but also propose a fast heuristic pipeline. Via a quantitative evaluation, we show that the heuristic is feasible even for large instances, while producing at most twice as many crossings as an optimal drawing in most cases.