What Have Innsbruck and Leipzig in Common? Extracting Semantics from Wiki Content

  • Sören Auer
  • Jens Lehmann
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4519)


Wikis are established means for the collaborative authoring, versioning and publishing of textual articles. The Wikipedia project, for example, succeeded in creating the by far largest encyclopedia just on the basis of a wiki. Recently, several approaches have been proposed on how to extend wikis to allow the creation of structured and semantically enriched content. However, the means for creating semantically enriched structured content are already available and are, although unconsciously, even used by Wikipedia authors. In this article, we present a method for revealing this structured content by extracting information from template instances. We suggest ways to efficiently query the vast amount of extracted information (e.g. more than 8 million RDF statements for the English Wikipedia version alone), leading to astonishing query answering possibilities (such as for the title question). We analyze the quality of the extracted content, and propose strategies for quality improvements with just minor modifications of the wiki systems being currently used.


Triple Pattern Common Sense Knowledge Collaborative Authoring MediaWiki Software Semantic Collaboration 
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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Copyright information

© Springer Berlin Heidelberg 2007

Authors and Affiliations

  • Sören Auer
    • 1
    • 2
  • Jens Lehmann
    • 1
  1. 1.Universität Leipzig, Department of Computer Science, Johannisgasse 26, D-04103 LeipzigGermany
  2. 2.University of Pennsylvania, Department of Computer and Information Science, Philadelphia, PA 19104USA

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