Fuzzy Representations in Rough Set Approximations

  • Michael Hadjimichael
  • S. K. Michael Wong
Conference paper
Part of the Workshops in Computing book series (WORKSHOPS COMP.)

Abstract

Frequently, knowledge systems represent information crisply. That is, for a given object in the database, and a given property (attribute-value pair), there is no uncertainty whether or not the object has that property. This certainty restricts expressive power. Therefore, we present here an approach to knowledge representation and rough set-based inductive learning using a fuzzy set representation of information. Specifically, we introduce the Fuzzy Property Set model, which is an enhancement of the Property Set model in which each object is represented by a collection of properties. In this fuzzy enhancement, it is possible to denote the degree to which an object has a particular property. Fuzzy rough set upper and lower approximations are defined using this model, as a basis for the inductive learning of concepts. Various similarity and distance measures can then be used to rank objects according their similarity to the upper or lower concept approximations.

Keywords

Fuzzy Representation Object Description Atomic Concept Fuzzy Property Knowledge Representation System 
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

© British Computer Society 1994

Authors and Affiliations

  • Michael Hadjimichael
    • 1
  • S. K. Michael Wong
    • 1
  1. 1.Department of Computer ScienceUniversity of ReginaReginaCanada

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