Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Ranking the Linked Data: the case of DBpedia - ICWE 2010

1,139 views

Published on

  • Be the first to comment

Ranking the Linked Data: the case of DBpedia - ICWE 2010

  1. 1. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Ranking the LinkedData: the case of DBpedia Roberto Mirizzi1, Azzurra Ragone1,2, Tommaso Di Noia1, Eugenio Di Sciascio1 1Politecnico di Bari Via Orabona, 4 70125 Bari (ITALY) 2University of Trento Via Sommarive, 14 38100 Trento (ITALY)
  2. 2. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Outline • Tags are all around • NOT (Not Only Tag): what is it? • NOT a look behind the curtains: – Ranking of RDF resources: an hybrid approach • Evaluation • Conclusion and Future Work
  3. 3. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Tags are all around
  4. 4. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Tag cloud and many more…
  5. 5. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Tagging: a double face Annotation phase Retrieval phase
  6. 6. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Problems with annotation • Insert as much as possible tags (time consuming): – different versions of the same tag to catch all the possible searches – Multilingual tags
  7. 7. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Problem with retrieval • Exactly (syntactic) match among tags: web service is different from web services, webservices,…
  8. 8. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Why not to use Semantic tags? Plugged into the Web 3.0 Disambiguation Relations among tags Machine understandable NOT: Not Only Tag http://sisinflab.poliba.it/not-only-tag/
  9. 9. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Demo • Let’s imagine to tag the book:
  10. 10. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 NOT http://sisinflab.poliba.it/not-only-tag/
  11. 11. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Smarter taggingAnnotationphaseRetrievalphase
  12. 12. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 What is behind NOT? • DBpedia graph exploration • Computation of similarity value between each pair of RDF resources using external information sources (search engines, bookmarking systems)
  13. 13. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 What is behind NOT? (II)
  14. 14. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 What is behind NOT? (III)
  15. 15. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 What is behind NOT? (IV) Semantic_Web XML-based_standards Knowledge_representation Data_management Internet_architecture Triplestores Folksonomy … … XML Computer_and_telecommunication_stantards Web_services User_interface_markup_languages Scalable_Vector_GraphicsMicroformats skos:subject skos:broaderCategoryArticle Legend …… … Resource Description Framework Microformat RDFa … …
  16. 16. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 DBpedia-Ranker: hybrid ranking ?r1 ?r2 isSimilar v hasValue )( ),( )( ),( ),( 2 21 1 21 21 rf rrf rf rrf rrsim        viceversaandrandrbetweenwikilink,2 saor viceverrandrbetweenkwikilin,1 randrbetweenwikilinkno,0 ),( 21 21 21 21 rrorewikilinkSc )( ),( ),( 2 12 21 rl rrl rroreabstractSc  Graph-based ranking External sources-based ranking
  17. 17. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Functional Architecture Back-end Query engine Storage Cloud Generator GUI Ext.InfoSources DBpedia Lookup Service Delicious Yahoo! Bing Graph Explorer SPARQL Context Analyzer Ranker Offline computation Linked Data graph exploration Rank nodes exploiting external information Store results as pairs of nodes together with their similarity Runtime Search Start typing a tag Query the system for relevant tags (corresponding to DBpedia resources) Show the semantic tag cloud 1 2 3 1 2 3 1 Offlinecomputation 2 3 1 2 3 GoogleGoogle Runtimesearch
  18. 18. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Evaluation We evaluate five different algorithms: 1. DBpediaRanker 2. DBpediaRanker minus Wikipedia info 3. DBpediaRanker minus ext info sources 4. Co-occurrence 5. Similarity Distance ),()()( ),( ),( 2121 21 21 rrfrfrf rrf rrcoOcc     )}(log),(min{loglog ),(log)(log),(logmax ),( 21 2121 21 rfrfN rrfrfrf rrngd   
  19. 19. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Evaluation (II) http://sisinflab.poliba.it/evaluation  50 volunteers Researchers in the ICT area 244 votes collected (on average 5 votes for each users) Time to vote: 1min and 40secs
  20. 20. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Evaluation (III) http://sisinflab.poliba.it/evaluation/data 3.91 - Good
  21. 21. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Conclusion • NOT *is* useful in the annotation phase: – suggestions of semantically related tags – Tags enrichment • NOT *is* useful in the retrieval phase: – Semantic match among tags
  22. 22. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Future Work
  23. 23. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Impakt Revolution http://sisinflab.poliba.it/impakt-revolution/
  24. 24. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Inspiration: Google Wonder Wheel Exploratory Search in Google… …nice, but there is no “semantics” in it. You can not discover new knowledge exploiting the meaning of a term (keyword/tag/query)
  25. 25. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 SWOC: Semantic Wonder Cloud http://sisinflab.poliba.it/semantic-wonder-cloud/index/
  26. 26. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Q&A a.ragone@poliba.it Thanks for being here on Friday! :-) http://sisinflab.poliba.it/not-only-tag/ http://sisinflab.poliba.it/semantic-wonder-cloud/index/ http://sisinflab.poliba.it/impakt-revolution/
  27. 27. 10th International Conference on Web Engineering, Vienna July 5-9, 2010 Conclusion  NOT: a tool for smarter tagging  Ranking algorithm for RDF graphs Future work  Test our algorithms with different domains  Extract more fine grained contexts  Enrich the extracted context using also relevant properties  Integrate our approach with real existing systems  Use the core system to automatically extract relevant tags (concepts) from a document (or from a collection of documents) exploiting tools for named entities extraction

×