Explicit representation of terms defined by counter examples

  • J. -L. Lassez
  • K. Marriott
Session 2 Logic Programming And Functional Programming
Part of the Lecture Notes in Computer Science book series (LNCS, volume 241)


Anti-unification guarantees the existence of a term which is an explicit representation of the most specific generalization of a collection of terms. This provides a formal basis for learning from examples. Here we address the dual problem of computing a generalization given a set of counter examples. Unlike learning from examples an explicit, finite representation for the generalization does not always exist. We show that the problem is decidable by providing an algorithm which, given an implicit representation will return a finite explicit representation or report that none exists. Applications of this result to the problem of negation as failure and to the representation of solutions to systems of equations and inequations are also mentioned.


Function Symbol Explicit Representation Implicit Representation Specific Generalization Ground Term 
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-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • J. -L. Lassez
    • 1
  • K. Marriott
    • 1
  1. 1.IBM Thomas J. Watson Research CenterYorktown Heights

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