In International Journal Human-Computer Studies 43, p.907-928. Substantial revision of paper presented at the International Workshop on Formal Ontology, March, 1993, Padova, Italy. Available as Technical Report KSL 93-04, Knowledge Systems Laboratory, Stanford University. Toward Principles for the Design of Ontologies Used for Knowledge Sharing Revision: August 23, 1993 Thomas R. Gruber Stanford Knowledge Systems Laboratory 701 Welch Road, Building C Palo Alto, CA 94304
[email protected] Recent work in Artificial Intelligence is exploring the use of formal ontologies as a way of specifying content-specific agreements for the sharing and reuse of knowledge among software entities. We take an engineering perspective on the development of such ontologies. Formal ontologies are viewed as designed artifacts, formulated for specific purposes and evaluated against objective design criteria. We describe the role of ontologies in supporting knowledge sharing activities, and then present a set of criteria to guide the development of ontologies for these purposes. We show how these criteria are applied in case studies from the design of ontologies for engineering mathematics and bibliographic data. Selected design decisions are discussed, and alternative representation choices and evaluated against the design criteria. Keywords: ontology, knowledge sharing, ontology design, ontological commitment, Knowledge Interchange Format, measurement theory 1. Introduction Several technical problems stand in the way of shared, reusable knowledge-based software. Like conventional applications, knowledge-based systems are based on heterogeneous hardware platforms, programming languages, and network protocols. However, knowledge-based systems pose special requirements for interoperability. Such systems operate on and communicate using statements in a formal knowledge representation.