1. Jiao Tao, Li Ding, Deborah L. McGuinness Tetherless World Constellation Rensselaer Polytechnic Institute Troy, NY, USA Instance Data Evaluation on the Semantic Web

2. Data Evaluation on the SW: State of the Art On the semantic web, instance data often accounts for orders of magnitude more data than ontology (Ding & Finin 2006). However most data evaluation work (Rocha et al. 1998) focuses on ontology evaluation, i.e., checking whether the ontologies correctly describe the domain of interests. There is very little, if any, work on evaluating the conformance between ontologies and instance data.

3. 1. Create domain knowledge as ontologies O (semantic expectations) Web O O D D 3. Instantiate ontologies as instance data D 4. Publish D O O 2. Acquire ontologies Does D follow the semantic expectations in O ? No syntax errors? Instance Data Evaluation on the Semantic Web Semantic expectation mismatches: (i) Logical inconsistencies (ii) Integrity issues

4. Generic Evaluation Process (GEP) Load instance data D –Is loading failing? Parse instance data D –Is D syntactically correct? Load referenced ontologies O = {O 1,O 2, …} –Is O i reachable? where O i defines the terms used by D. Inspect logical inconsistencies in D –Is O i logically consistent? –Merge all consistent referenced ontologies into O' –Are D+O’ logically consistent? Inspect integrity issues in D –Compute DC = INF(D,O') which includes all triples in D and O', and all inferred sub-class/sub-property relations –Is there any integrity issue in D?

5. Integrity Issues Unexpected Individual Type (UIT) Issue –rdfs:domain –rdfs:range –owl:allValuesFrom Redundant Individual Type (RIT) Issue Non-specific Individual Type (NSIT) Issue Missing Property Value (MPV) Issue –owl:cardinality –owl:minCardinality Excessive Property Value (EPV) Issue –owl:cardinality –owl:maxCardinality

6. Make sure all instances of wine have a Maker Example: MPV

7. SPARQL Solutions for Integrity Issue Detection

8. Implementation and Evaluation Demo: TW OIE Service http://onto.rpi.edu/demo/oie/ http://onto.rpi.edu/demo/oie/ Comparative experiment results

9. References T. Berners-Lee, J. Hendler, and O. Lassila, The Semantic Web: A New Form of Web Content that Is Meaningful to Computers Will Unleash a Revolution of New Possibilities, Scientific American, pp. 34–43, 2001. J. Davies, M. Lytras, and A. Sheth, Semantic-Web-Based Knowledge Management, IEEE Internet Computing, Vol. 11, No. 5, pp. 14-6, 2007. L. Ding, and T. Finin, Characterizing the Semantic Web on the Web, ISWC, pp. 242-257, 2006. R. A. Rocha, S. M. Huff, P. J. Haug, D. A. Evans, and B. E. Bray, Evaluation of a Semantic Data Model for Chest Radiology: Application of a New Methodology, Methods of Information in Medicine, Vol. 37, No.4-5, pp. 477-490, 1998. D. L. McGuinness and P. Pinheiro da Silva. Explaining Answers from the Semantic Web: The Inference Web Approach. Journal of Web Semantics. Vol.1 No.4., pp 397-413, 2004.