A German Natural Language Interface for Semantic Search

  • Irina Deines
  • Dirk Krechel
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7774)


Semantic data is the key for an efficient information retrieval. It relies on a well-defined structure and enables automated processing. Therefore, more and more ontologies are specified, extended and interlinked. By now, only the query language SPARQL provides a precise access to semantic data. Since most common users are overstrained in formulating queries, which satisfy the structure of semantic data, more search-interface approaches emerge aiming at good usability and correct answers. We implemented a Natural Language Interface (NLI), that answers questions formulated in German natural language. In order to query the domain ontology, the user query is translated into SPARQL first. Since domain-ontology resources are required for the SPARQL-query formulation, this paper introduces an approach for the identification of resources in user query. We show a path-based identification of semantically similar resources and a similarity measure. After running 100 test questions, our system achieves a precision and recall of 66%.


Semantic Similarity Resource Description Framework Domain Ontology Lexical Entry User Query 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. 1.
    Antoniou, G., van Harmelen, F.: A Semantic Web Primer, 2nd edn. Cooperative Information Systems. The MIT Press (2008)Google Scholar
  2. 2.
    W3C World Wide Web Consortium: Resource Description Framework (RDF). Website, (visited on September 14, 2010)
  3. 3.
    Bizer, C., Heath, T., Berners-Lee, T.: Linked Data – The Story So Far. International Journal on Semantic Web and Information Systems 5(3), 1–22 (2009)CrossRefGoogle Scholar
  4. 4.
    Prud’hommeaux, E., Seaborne, A.: SPARQL Query Language for RDF. Website, (visited on September 14, 2010)
  5. 5.
    Kaufmann, E., Bernstein, A.: How Useful Are Natural Language Interfaces to the Semantic Web for Casual End-Users? In: Aberer, K., Choi, K.-S., Noy, N., Allemang, D., Lee, K.-I., Nixon, L.J.B., Golbeck, J., Mika, P., Maynard, D., Mizoguchi, R., Schreiber, G., Cudré-Mauroux, P. (eds.) ISWC/ASWC 2007. LNCS, vol. 4825, pp. 281–294. Springer, Heidelberg (2007)CrossRefGoogle Scholar
  6. 6.
    Heim, P., Ertl, T., Ziegler, J.: Facet Graphs: Complex Semantic Querying Made Easy. In: Aroyo, L., Antoniou, G., Hyvönen, E., ten Teije, A., Stuckenschmidt, H., Cabral, L., Tudorache, T. (eds.) ESWC 2010, Part I. LNCS, vol. 6088, pp. 288–302. Springer, Heidelberg (2010)CrossRefGoogle Scholar
  7. 7.
    Damljanovic, D., Agatonovic, M., Cunningham, H.: Natural Language Interfaces to Ontologies: Combining Syntactic Analysis and Ontology-Based Lookup through the User Interaction. In: Aroyo, L., Antoniou, G., Hyvönen, E., ten Teije, A., Stuckenschmidt, H., Cabral, L., Tudorache, T. (eds.) ESWC 2010, Part I. LNCS, vol. 6088, pp. 106–120. Springer, Heidelberg (2010)CrossRefGoogle Scholar
  8. 8.
    Semantic Computing Group, CITEC, Bielefeld University and the Knowledge Media Institute (KMi), Open University: Proceedings of 1st Workshop on Question Answering over Linked Data (QALD-1), Collocated with the 8th Extended Semantic Web Conference (ESWC 2011), Heraklion, Greece (June 2011)Google Scholar
  9. 9.
    Lehmann, J., Bizer, C., Kobilarov, G., Auer, S., Becker, C., Cyganiak, R., Hellmann, S.: DBpedia - a crystallization point for the web of data. Journal of Web Semantics 7(3), 154–165 (2009)CrossRefGoogle Scholar
  10. 10.
    Kaufmann, E., Bernstein, B., Zumstein, R.: Querix: A natural language interface to query ontologies based on clarification dialogs. In: In: 5th ISWC, pp. 980–981. Springer (2006)Google Scholar
  11. 11.
    Wang, C., Xiong, M., Zhou, Q., Yu, Y.: PANTO: A Portable Natural Language Interface to Ontologies. In: Franconi, E., Kifer, M., May, W. (eds.) ESWC 2007. LNCS, vol. 4519, pp. 473–487. Springer, Heidelberg (2007)CrossRefGoogle Scholar
  12. 12.
    Princeton University: Princeton University ’About WordNet’. Website, (visited on November 7, 2011)
  13. 13.
    University of Tübingen: GermaNet - A German Wordnet. Website, (visited on November 7, 2011)
  14. 14.
    Rafferty, A.N., Manning, C.D.: Parsing three German treebanks: lexicalized and unlexicalized baselines. In: Proceedings of the Workshop on Parsing German, PaGe 2008, pp. 40–46. Association for Computational Linguistics (2008)Google Scholar
  15. 15.
    Schmid, H.: Improvements in Part-of-Speech Tagging with an Application to German. In: Proceedings of the ACL SIGDAT-Workshop, pp. 47–50 (1995)Google Scholar
  16. 16.
    Ott, N.: BananaSplit - Dictionary-based Compound Splitter for German Platform. Website, (visited on February 6, 2012)
  17. 17.
    Moldovan, D.I., Harabagiu, S.M., Pasca, M., Mihalcea, R., Girju, R., Goodrum, R., Rus, V.: The Structure and Performance of an Open-Domain Question Answering System. In: ACL. ACL (2000)Google Scholar
  18. 18.
    Wu, Z., Das, S., Annamalai, M., Murray, C., Beauregard, B.: Oracle Semantic Technologies Inference Best Practices with RDFS/OWL. Oracle (2008)Google Scholar
  19. 19.
    Kuc, R.: Apache Solr 3.1 Cookbook. Packt Publishing (2011)Google Scholar
  20. 20.
    Delbru, R., Toupikov, N., Catasta, M., Tummarello, G.: A Node Indexing Scheme for Web Entity Retrieval. In: Aroyo, L., Antoniou, G., Hyvönen, E., ten Teije, A., Stuckenschmidt, H., Cabral, L., Tudorache, T. (eds.) ESWC 2010, Part II. LNCS, vol. 6089, pp. 240–256. Springer, Heidelberg (2010)CrossRefGoogle Scholar
  21. 21.
    McCrae, J., Spohr, D., Cimiano, P.: Linking Lexical Resources and Ontologies on the Semantic Web with Lemon. In: Antoniou, G., Grobelnik, M., Simperl, E., Parsia, B., Plexousakis, D., De Leenheer, P., Pan, J. (eds.) ESWC 2011, Part I. LNCS, vol. 6643, pp. 245–259. Springer, Heidelberg (2011)CrossRefGoogle Scholar
  22. 22.
    Pedersen, T., Patwardhan, S., Michelizzi, J.: WordNet::Similarity: Measuring the Relatedness of Concepts. In: Proceedings of the Demonstration Papers at HLT-NAACL (2004)Google Scholar
  23. 23.
    Manning, C.D., Raghavan, P., Schütze, H.: Introduction to Information Retrieval. Cambridge University Press (2008)Google Scholar
  24. 24.
    Cimiano, P., Haase, P., Heizmann, J.: Porting natural language interfaces between domains: an experimental user study with the orakel system. In: Proceedings of the 12th International Conference on Intelligent User Interfaces (2007)Google Scholar
  25. 25.
    Kübler, S., Prokic, J., Groningen, R.: Why is German dependency parsing more reliable than constituent parsing? In: Proceedings of the Fifth Workshop on Treebanks and Linguistic Theories, TLT (2006)Google Scholar
  26. 26.
    Nivre, J., Hall, J., Nilsson, J., Chanev, A., Eryigit, G., Kübler, S., Marinov, S., Marsi, E.: Maltparser: A language-independent system for data-driven dependency parsing. Natural Language Engineering 13(2), 95–135 (2007)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Irina Deines
    • 1
  • Dirk Krechel
    • 1
  1. 1.University of Applied Sciences RheinMainGermany

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