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Explore the application of Description Logic and Fuzzy Logic models in Web Modelling, including Bayesian networks and user preference modeling. Learn about handling imperfections and uncertainty in ontology languages. Discover methods for global preference aggregation and top-k answers. Join A. Eckhardt and P. Vojtáš on this insightful journey into enhancing web modelling.
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Towards ontology language handling imperfection Alan Eckhardt, Peter Vojtáš WIKT 2006
DL and Web modelling (časť prezentácie z ISWC06) • DL basis for OWL • Value restriction has to be reconsidered • EL DL sufficient for applications • EL querying in poly time • Extension to user preference modelse.g. a user looking for a cheap hotel close to a beach • Aggregation of particular attribute preferences to global preference • Top-k answers A.Eckhardt, P. Vojtáš
Uncertainty in Web Modelling • Probabilistic models in SW • Fuzzy logic models SW • Fuzzy EL - fuzzy concepts • - crisp roles • - fuzzy aggregation • Enables concepts like @( price.cheap, distance.close) • Problem of learning @ for each user A.Eckhardt, P. Vojtáš
Description logic – classical AL* interpretation EL A.Eckhardt, P. Vojtáš
Description logic – full fuzzification – U. Straccia syntax Fuzzy interpretation Which t-norm t-conorm? A.Eckhardt, P. Vojtáš
Bayesian networks (slide z článku s M. Vomlelovou) • Graph represents relations between variables • Conditional probabilities • Typical use: • We know: A=2, C=2 • We ask for: P(B|A=2,C=2) A.Eckhardt, P. Vojtáš
From FILP, IGAP to BN (slide z článku s M. Vomlelovou a T. Horváthom) A.Eckhardt, P. Vojtáš
Bayesian EL DL and others • Concepts are r. v. over preference scale • Roles are crisp / certain • Aggregation = combination function • Integrated with fEL, classical EL , … A.Eckhardt, P. Vojtáš
Conclusion • Sharing ideas • Ideas supported by an analogy working in LP and simple experiments • Further development of formal model experiments OWL extension • Questions, comments, … A.Eckhardt, P. Vojtáš