Canonical Forms and Similarity of Complex Concepts for Improved Ontology Alignment

Modern ontology languages such as the Web Ontology Language (OWL) allow defining complex concepts that involve restrictions, Boolean combinations, and exhaustive enumeration of individuals.Many of the current ontology alignment algorithms either do not consider the complex concepts in their alignment procedures or model them naively, thereby producing a possibly incomplete alignment. We introduce axiomatic and graphical canonical forms for modeling value and cardinality restrictions and Boolean combinations, and present a way of measuring the similarity between these complex concepts in their canonical forms. We integrate our approach in multiple ontology alignment algorithms. Our results indicate a significant improvement in the F-measure of the alignment. However, this improvement is at the expense of increased run time due to the additional concepts modeled.