StarLion: Auto-configurable Layouts for Exploring Ontologies

The visualization of ontologies is a challenging task especially if they are large. We will demonstrate StarLion, a system providing exploratory visualizations which enhance the user understanding. StarLion combines many of the existing visualization methods with some novel features for providing better 2D layouts. Specifically, one distinctive feature of StarLion is the provision of Star-like graphs of variable radius whose layout is derived by a Force Directed Placement algorithm (FDPA) specially adapted for RDF Schemas. This approach enables users to gradually explore and navigate through the entire ontology without overloading them. StarLion can also handle multiple namespaces, a very useful feature for assisting the understanding of interdependent ontologies. Another distinctive characteristic of StarLion is the provision of a novel method for configuring automatically the FDPA parameters based on layout quality metrics, and the provision of an interactive configuration method offered via an intuitive tool-bar.