Generalization under implication by using or-introduction

  • Peter Idestam-Almquist
Research Papers Inductive Logic Programming
Part of the Lecture Notes in Computer Science book series (LNCS, volume 667)


In the area of inductive learning, generalization is a main operation. Already in the early 1970's Plotkin described algorithms for computation of least general generalizations of clauses under θ-subsumption. However, there is a type of generalizations, called roots of clauses, that is not possible to find by generalization under θ-subsumption. This incompleteness is important, since almost all inductive learners that use clausal representation perform generalization under θ-subsumption.

In this paper a technique to eliminate this incompleteness, by reducing generalization under implication to generalization under θ-subsumption, is presented. The technique is conceptually simple and is based on an inference rule from natural deduction, called or-introduction. The technique is proved to be sound and complete, but unfortunately it suffers from complexity problems.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Peter Idestam-Almquist
    • 1
  1. 1.Department of Computer and Systems SciencesStockholm UniversityKistaSweden

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