Making entailment set changes explicit improves the understanding of consequences of ontology authoring actions

Abstract

The consequences of adding or removing axioms are difficult to apprehend for ontology authors using the Web Ontology Language (OWL). Consequences of modelling actions range from unintended inferences to outright defects such as incoherency or even inconsistency. One of the central ontology authoring activities is verifying that a particular modelling step has had the intended consequences, often with the help of reasoners. For users of Protégé, this involves, for example, exploring the inferred class hierarchy. We explore the hypothesis that making changes to key entailment sets explicit improves verification compared to the standard static hierarchy/frame-based approach. We implement our approach as a Protégé plugin and conduct an exploratory study to isolate the authoring actions for which users benefit from our approach. In a second controlled study we address our hypothesis and find that, for a set of key authoring problems, making entailment set changes explicit improves the understanding of consequences both in terms of correctness and speed, and is rated as the preferred way to track changes compared to a static hierarchy/frame-based view.