When owl:sameAs Isn’t the Same: An Analysis of Identity in Linked Data

  • Harry Halpin
  • Patrick J. Hayes
  • James P. McCusker
  • Deborah L. McGuinness
  • Henry S. Thompson
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6496)


In Linked Data, the use of owl:sameAs is ubiquitous in interlinking data-sets. There is however, ongoing discussion about its use, and potential misuse, particularly with regards to interactions with inference. In fact, owl:sameAs can be viewed as encoding only one point on a scale of similarity, one that is often too strong for many of its current uses. We describe how referentially opaque contexts that do not allow inference exist, and then outline some varieties of referentially-opaque alternatives to owl:sameAs. Finally, we report on an empirical experiment over randomly selected owl:sameAs statements from the Web of data. This theoretical apparatus and experiment shed light upon how owl:sameAs is being used (and misused) on the Web of data.


linked data identity coreference 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Harry Halpin
    • 1
  • Patrick J. Hayes
    • 2
  • James P. McCusker
    • 3
  • Deborah L. McGuinness
    • 3
  • Henry S. Thompson
    • 1
  1. 1.School of InformaticsUniversity of EdinburghEdinburghUK
  2. 2.Institute for Human and Machine CognitionPensacolaUSA
  3. 3.Tetherless World Constellation, Department of Computer ScienceRensselaer Polytechnic InstituteTroyUSA

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