Renaming a set of non-horn clauses

  • Xumin Nie
  • Qing Guo
Communications Session 7B Logic for AI
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1325)


Several extensions of the logic programming language Prolog to non-Horn clauses use case analysis to handle non-Horn clauses. In this paper, we present analytical and empirical evidence that, by making a set of clauses less “non-Horn” using predicate renaming, the performance of these case-analysis based procedures can be improved significantly. In addition, we will investigate the problem of efficiently constructing a predicate renaming that reduces the degree of “non-Hornness” of a clause set by the maximum. We will show that the problem of finding a predicate renaming to achieve minimal “non-Hornness” is NP-complete.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Xumin Nie
    • 1
  • Qing Guo
    • 2
  1. 1.Department of Computer ScienceWichita State UniversityWichitaUSA
  2. 2.Department of Computer ScienceState University of New YorkAlbanyUSA

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