Representing exceptions in rule-based systems

  • P. L. Tan
  • T. S. Dillon
  • J. Zeleznikow
Knowledge Acquisition And Representation
Part of the Lecture Notes in Computer Science book series (LNCS, volume 406)


Making inferences and decisions in an imprecise and changing world limits the potential leverage of a system, particularly, in occurrence of exceptions. Many rule-based systems which make inferences using rules attempt to deal with expected exceptions by augmenting the rules in the knowledge base. The result is a whole tree of rules which widens the search space of a goal. This paper introduces several kinds of exceptions and presents a methodology for representing exceptions at the object level and meta level of rule-based systems. The proposed approach accommodates instance exceptions as well as assertion exceptions, hence allowing for the recognition of exception rules as distinct from the normal rules in rule-based systems.

Keywords and phrases

object-level rules meta-level rules rule model exceptions 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • P. L. Tan
    • 1
  • T. S. Dillon
    • 1
  • J. Zeleznikow
    • 1
  1. 1.Department of Computer ScienceLa Trobe UniversityBundooraAustralia

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