How do we measure and improve the quality of a hierarchical ontology?

Hierarchical ontologies enable organising information in a human–machine understandable form, but constructing them for reuse and maintainability remains difficult. Often supporting tools available lack formal methodological underpinning and their developers are not supported by any concomitant metrics. The paper presents a formal underpinning to provide quality metrics of a taxonomy hierarchical ontology and proposes a methodology for semi-automatic building of maintainable taxonomies. Users provide terms to be used to describe different ontological elements as well as their attributes and their ranges of values. The methodology uses the formalised metrics to assess the quality of the users input and proposes changes according to given quality constraints. The paper illustrates the metrics and the methodology in constructing and repairing two medium size well-known taxonomies.

► We first ask “How Good is Your Hierarchical Ontology?” ► We present a qualitative evaluation framework to answer this question. ► We then ask “Can We Improve/Repair any of Shortcomings of the Ontology Automatically?” ► We then present two algorithms that use the formal evaluation framework and evaluate the algorithms on two cases studies.