Stratified Negation in RDF Rules: A Correct Approach
Aus International Center for Computational Logic
Stratified Negation in RDF Rules: A Correct Approach
Vortrag von Nils Küchenmeister
- Veranstaltungsort: APB 3027
- Beginn: 22. Oktober 2026 um 11:30
- Ende: 22. Oktober 2026 um 12:00
- Forschungsgruppe: Wissensbasierte Systeme
- Event series: Research Seminar Logic and AI
- iCal
Combining RDF rule languages, such as N3 or SHACL Rules, with default negation is challenging. Existing methods to stratify negation often fail for RDF rules, since individual triples do not carry enough information to meaningfully restrict potential dependencies. Blank nodes in rule heads further complicate the matter, since the order of rule applications may determine whether new values are created, which in turn can change the applicability of rules with negation. To solve these open problems, we propose chain stratification as a robust new condition that guarantees a well-behaved semantics for RDF rules with negation, and existential rules in general. Our condition combines an elaborate analysis of potential multistep derivations with a mechanism for using integrity constraints to discard impossible cases. Applying rules in any order that respects chain stratification is guaranteed to derive an RDF graph that is unique, lean, and justified under the usual negation-as-failure semantics. To show the practicality, we also provide a prototype implementation.
