1. April 23, 2007McGuinness NIST Interoperability Week One Ontology Spectrum Perspective Deborah L. McGuinness Acting Director & Senior Research Scientist Knowledge Systems, Artificial Intelligence Laboratory Stanford University http://www.ksl.stanford.edu/people/dlm/

2. April 23, 2007McGuinness NIST Interoperability Week Background AAAI 1999 panel on ontologies generated a discussion on how inclusive we should be when referring to something as an ontology. Panelists: Gruninger, Lehmann, McGuinness, Uschold, Welty generated one perspective on an ontology spectrum. During this time I was crawling the web for naturally occurring artifacts that some called ontologies, thus analyzing (selected) empirical data. McGuinness wrote a paper expanding upon the spectrum view and giving examples of how something at any point on this spectrum might be used: Deborah L. McGuinness. ``Ontologies Come of Age''. In Dieter Fensel, Jim Hendler, Henry Lieberman, and Wolfgang Wahlster, editors. Spinning the Semantic Web: Bringing the World Wide Web to Its Full Potential. MIT Press, 2003. www.ksl.stanford.edu/people/dlm/papers/ontologies-come-of- age-abstract.html www.ksl.stanford.edu/people/dlm/papers/ontologies-come-of- age-abstract.html

3. April 23, 2007McGuinness NIST Interoperability Week Ontology Spectrum Catalog/ ID Selected Logical Constraints (disjointness, inverse, …) Terms/ glossary Thesauri narrower term relation Formal is-a Frames (properties) Informal is-a Formal instance Value Restrs. General Logical constraints Originally from AAAI 1999- Ontologies Panel by Gruninger, Lehmann, McGuinness, Uschold, Welty; – updated by McGuinness. Description in: www.ksl.stanford.edu/people/dlm/papers/ontologies-come-of-age-abstract.html

4. April 23, 2007McGuinness NIST Interoperability Week Some uses of Ontologies Simple ontologies (taxonomies) provide: Controlled shared vocabulary (search engines, authors, users, databases, programs/agents all speak same language) Site Organization and Navigation Support Expectation setting (left side of many web pages) Umbrella Upper Level Structures (for extension) Browsing support (tagged structures such as Yahoo!) Search support (query expansion approaches such as FindUR, e-Cyc) Sense disambiguation

5. April 23, 2007McGuinness NIST Interoperability Week Uses of Ontologies II Consistency Checking Completion Interoperability Support Support for validation and verification testing Configuration support Structured, surgical comparative customized search Generalization / Specialization … Foundation for expansion and leverage

6. April 23, 2007McGuinness NIST Interoperability Week Take Home Message Relatively simple ontologies can provide significant value to many kinds of applications A view of ontologies as a spectrum has been useful as a way of introducing ontologies to a broad range of users An expressiveness spectrum has been a useful pedagogical tool While we may choose to make a many- dimensional spectrum, we may consider expressiveness as an important dimension