Relaxing RDF queries based on user and domain preferences

  • Peter DologEmail author
  • Heiner Stuckenschmidt
  • Holger Wache
  • Jörg Diederich


Research in cooperative query answering is triggered by the observation that users are often not able to correctly formulate queries to databases such that they return the intended result. Due to lacking knowledge about the contents and the structure of a database, users will often only be able to provide very broad queries. Existing methods for automatically refining such queries based on user profiles often overshoot the target resulting in queries that do not return any answer. In this article, we investigate methods for automatically relaxing such over-constrained queries based on domain knowledge and user preferences. We describe a framework for information access that combines query refinement and relaxation in order to provide robust, personalized access to heterogeneous resource description framework data as well as an implementation in terms of rewriting rules and explain its application in the context of e-learning systems.


Query relaxation User modeling Preferences ECA rules 


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Peter Dolog
    • 1
    Email author
  • Heiner Stuckenschmidt
    • 2
  • Holger Wache
    • 3
  • Jörg Diederich
    • 4
  1. 1.Department of Computer ScienceAalborg UniversityAalborgDenmark
  2. 2.Universität Mannheim - Institut für InformatikMannheimGermany
  3. 3.School of BusinessUniversity of Applied Sciences, Northwestern Switzerland (FHNW)OltenSwitzerland
  4. 4.Forschungszentrum L3SLeibniz Universität HannoverHannoverGermany

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