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Extensions of Semantic web modeling towards ordering of query results J. Pokorný (Charles University, Prague), P. Vojtáš (Šafárik University, Košice)

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Presentation on theme: "Extensions of Semantic web modeling towards ordering of query results J. Pokorný (Charles University, Prague), P. Vojtáš (Šafárik University, Košice)"— Presentation transcript:

1 Extensions of Semantic web modeling towards ordering of query results J. Pokorný (Charles University, Prague), P. Vojtáš (Šafárik University, Košice)

2 Vienna June 20th, 2005W3C and Semantic Web2 Motivation – user looking for best (top-k) objects Same data – different problems and solutions - Kossmanns skylines - Fagins threshold algorithm - fuzzy logic programming Learning of users aggregation DL: Value or existential restrictions Fuzzy Description logic EL Page Content Rank Galois - Tukey connections – Questions and Answers Conclusions Outline J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

3 Vienna June 20th, 2005W3C and Semantic Web3 Skyline of hotels: minimize price (x-axis) and distance to beach (y-axis) Skyline of buildings D. Kossmann et al. - Institute for Information Systems - DCS ETH Zurich Find a good hotel J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

4 Vienna June 20th, 2005W3C and Semantic Web4 Access multimedia data – red – inherently fuzzy Compound queries – red and round – aggregate NY restaurant – good, inexpensive, close - Zagat-Review web site gives rating - NYT web site gives prices - MapQuest gives distances … aggregate Relevant answers wrt users intention – best, top-k J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results R. Fagin. Combining fuzzy information: an Overview. SIGMOD Record 31,2002 Güntzer et al. Optimizing Multi-Feature Queries for Image Databases, VLDB00 Fuzzy …

5 Vienna June 20th, 2005W3C and Semantic Web5 J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results Combining fuzzy…

6 Vienna June 20th, 2005W3C and Semantic Web6 Continuity, fixpoint, completeness, similarity, PV. Fuzzy logic programming. Fuzzy Sets and Systems. 124,3 (2001) Need not be equivalent to Our solution Disjunction or aggregation? Logic programming in extensional fuzzy logic in narrow sense J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

7 Vienna June 20th, 2005W3C and Semantic Web7 Resource Representation Hotel, restaurant, product, service,… Object - attribute Multimedia, pictures,… color spectra, texture,… Texts vector, dependency tree,…. User Query Context, classification, preference ideal object, text, …. Models - what is the best Databases - small, medium, large model-proof theoretic semantics Metric - closer is better Vectors - smaler angle is better Bayes - more probable is better Multicriterial decision Price function - optimization Fuzzy logic - comparative notion of truth – higher TV is better - semantics Same data – different problems – different solutions J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

8 Vienna June 20th, 2005W3C and Semantic Web8 Deduction Abduction Induction Learning how to combine particular attribute score Into global score FILP Other inductive methods – on same data?? Declarative query languages / J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

9 Vienna June 20th, 2005W3C and Semantic Web9 Gradually classified data – input for learning – synthetic data J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

10 Vienna June 20th, 2005W3C and Semantic Web10 Add to background knowledge p(d) d E(e 2 ) THEN f m (e 1 ) f m (e 2 ) P. Vojtáš, T. Horváth, S. Krajči, R. Lencses. An ILP model for a monotone graded classification problem. Kybernetika 40,3 (2004) Learning with qualitative constraint – monotonicity and the problem formulation J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

11 Vienna June 20th, 2005W3C and Semantic Web11 J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results The aggregation function

12 Vienna June 20th, 2005W3C and Semantic Web12 Unicode RDF + RDFSchema ontology logic proof URI XML + name spaces + XMLSchema optimisation security trust Semantic web according to Tim Berners-Lee et al Machine processing J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

13 Vienna June 20th, 2005W3C and Semantic Web13 J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results F. Baader, S. Brandt, C. Lutz. Pushing the EL Envelope, 2005 Description logic FL 0 …allows for value restriction r.C … when clarifying the logical status of property arcs in semantic networks and slots in frames – the decision was taken – that arcs/slots should be read as value restrictions rather than existential restrictions r.C tractability turned out to be unattainable DL – value or existential restriction

14 Vienna June 20th, 2005W3C and Semantic Web14 J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results F. Baader, S. Brandt, C. Lutz. Pushing the EL Envelope, 2005 Recently, the choice of value restriction as a sine qua non of DL has been reconsidered … EL – allowing conjunction and existential restrictions … Better algorithmic properties In applications the expressive power of EL sufficient DL – value or existential restriction

15 Vienna June 20th, 2005W3C and Semantic Web15 good hotel neither price.cheap distance.close nor price.cheap distance.close We need an price.cheap, distance.close) J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results Fuzzy EL Description logic

16 Vienna June 20th, 2005W3C and Semantic Web16 PAGE CONTENT RANK categories of Web data mining (Pal et al, 2002): Web Structure Mining (WSM), Web Usage Mining (WUM), Web Content Mining (WCM). Here: WCM refers broadly to the process of uncovering interesting and potentially useful knowledge from web contents/documents J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

17 Vienna June 20th, 2005W3C and Semantic Web17 The PCR method in sketch Principle: PCR enables to classify pages from a set R q of pages retrieved as the result of a conjunctive Boolean query q. Relevance measure computation: –vector models: comparing the query vector with the page vector –here: it is derived only from importances of terms that the page contains The core of PCR is based on an evaluation of terms from R q according to their occurrences in pages and their semantic properties. Final term evaluation is calculated from the parameters gained by an adapted backpropagation neural network. A set of training examples (terms) is obtained from the set R q0, where q 0 is a starting query. The relevance of the terms to the given topic has been assigned manually. Pokorný, Smižanský. IASTED AC 2005 J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

18 Vienna June 20th, 2005W3C and Semantic Web18 PCR Concluded To validate the hypothesis PCR identifies pages which are more significant with respect to their content and better explains given topic than the PageRank algorithm. we need more experiments. Issues: time complexity of obtaining R q,n Solution: PCR module on the side of the search engine Development: ranking clusters continuous adaptability of the system depending on user reactions more semantics - phrases J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

19 Vienna June 20th, 2005W3C and Semantic Web19 Galois Tukey connections P. Vojtáš. Gen. Galois-Tukey connections Israel Math.Conf.Proc. 6 (1993) A. Blass. Questions and answers, Proc. Linear Logic, J.Y. Girard, LMSLN 222, 1995 Questions 1 Questions 2 Answers 1 Answers 2 Correct 1 wrt KB 1 Correct 2 wrt KB 2 f(q 1 ) Correct 2 a 2 then q 1 Correct 1 g(a 2 ) fg J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

20 Vienna June 20th, 2005W3C and Semantic Web20 Questions 1 Questions 2 Answers 1 Answers 2 _Correct 1 _ _Correct 2 _ (h(q 1 ) C 3 a 3 ) and (f(q 1, a 3 ) Correct 2 a 2 ) then q 1 Correct 1 g(a 2 ) Q 3 _C 3 _ A 3 h f g Galois-Tukey connections, iterated forcing and querying with advice J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

21 Vienna June 20th, 2005W3C and Semantic Web21 J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results Marie-Christine Rousset: Small can be beautiful in the semantic web, ISWC 2004 We need modeling tools for - Ordering of results - Aggregation of particular attribute score into global Conclusions Optimisation Proof Logic Ontology RDF + RDFS XML … User dependent

22 Vienna June 20th, 2005W3C and Semantic Web22 Thank you J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results


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