Ontologies for Knowledge Graphs: Breaking the Rules

Talk by Veronika Thost

Location: APB 3027
Start: 28. September 2016 at 2:50 pm
End: 28. September 2016 at 3:50 pm
Research group: Knowledge-Based Systems
Event series: KBS Seminar
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Large-scale knowledge graphs (KGs) are widely used in industry and academia, and provide excellent use-cases for ontologies. We find, however, that popular ontology languages, such as OWL and Datalog, cannot express even the most basic relationships on the normalised data format of KGs. Existential rules are more powerful, but may make reasoning undecidable. Normalising them to suit KGs often also destroys syntactic restrictions that ensure decidability and low complexity. We study this issue for several classes of existential rules and derive new syntactic criteria to recognise well-behaved rule-based ontologies over KGs.