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Extensions of Semantic web modeling towards ordering of query results

Extensions of Semantic web modeling towards ordering of query results. J. Pokorný (Charles University, Prague), P. Vojtáš (Šafárik University, Košice). Outline. Motivation – user looking for best (top-k) objects Same data – different problems and solutions

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Extensions of Semantic web modeling towards ordering of query results

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

  2. Outline Motivation – user looking for best (top-k) objects Same data – different problems and solutions - Kossmann’s skylines - Fagin’s threshold algorithm - fuzzy logic programming Learning of user’s aggregation function @ DL: Value or existential restrictions Fuzzy Description logic ELwith @ Page Content Rank Galois - Tukey connections – Questions and Answers Conclusions W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

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

  4. Fuzzy … 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 R. Fagin. Combining fuzzy information: an Overview. SIGMOD Record 31,2002 Güntzer et al. Optimizing Multi-Feature Queries for Image Databases, VLDB’00 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  5. Combining fuzzy… W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  6. Logic programming in extensional fuzzy logic in narrow sense Need not be equivalent to Our solution Disjunction or aggregation? Continuity, fixpoint, completeness, similarity, PV. Fuzzy logic programming. Fuzzy Sets and Systems. 124,3 (2001) 361-370 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  7. Same data – different problems – different solutions ResourceRepresentation Hotel, restaurant, product, service,… Object - attribute Multimedia, pictures,… color spectra, texture,… Texts vector, dependency tree,…. UserQuery 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 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

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

  9. Gradually classified data – input for learning – synthetic data W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  10. Learning with qualitative constraint – monotonicity and the problem formulation Add to background knowledge p(d) ← d<c & p(c) Graded ILP problem formulation • E(e1) < E(e2) THEN fm (e1) ≤ fm (e2) and • E(e1) > E(e2) THEN fm (e1) ≥ fm (e2) P. Vojtáš, T. Horváth, S. Krajči, R. Lencses. An ILP model for a monotone graded classification problem. Kybernetika 40,3 (2004) 317-332 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  11. The aggregation function W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

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

  13. DL – value or existential restriction Description logic FL0 …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 F. Baader, S. Brandt, C. Lutz. Pushing the EL Envelope, 2005 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  14. DL – value or existential restriction 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 F. Baader, S. Brandt, C. Lutz. Pushing the EL Envelope, 2005 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  15. Fuzzy EL Description logic with @ good hotel neither ∃ price.cheap ⊓ ∃distance.close nor ∃ price.cheap ⊔ ∃distance.close We need an extension @(∃ price.cheap, ∃distance.close) W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  16. 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 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  17. The PCR method in sketch Principle: PCR enables to classify pages from a set Rq 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 Rq 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 Rq0, where q0 is a starting query. The relevance of the terms to the given topic has been assigned manually. Pokorný, Smižanský. IASTED AC 2005 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  18. 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 Rq,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 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  19. Galois Tukey connections Questions1 Answers1 Correct1 wrt KB1 f g Answers2 Questions2 Correct2 wrt KB2 f(q1) Correct2 a2 then q1 Correct1 g(a2) P. Vojtáš. Gen. Galois-Tukey connections Israel Math.Conf.Proc. 6 (1993) 619-643 A. Blass. Questions and answers, Proc. Linear Logic, J.Y. Girard, LMSLN 222, 1995 W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

  20. Galois-Tukey connections, iterated forcing and querying with advice Questions1 Answers1 _Correct1_ h g Q3 _C3_ A3 f Questions2 Answers2 _Correct2_ (h(q1) C3 a3) and (f(q1,a3) Correct2 a2) then q1 Correct1 g(a2) W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

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

  22. Thank you W3C and Semantic Web J. Pokorný, P. Vojtáš. Extensions of Semantic web modeling towards ordering of query results

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