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Rough Approximations under Level Fuzzy Sets

  • W. -N. Liu
  • JingTao Yao
  • Yiyu Yao
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3066)

Abstract

The combination of fuzzy set and rough set theories lead to various models. Functional and set approaches are two categories based on different fuzzy representations. In this paper, we study rough approximations based on the notion of level fuzzy sets. Two rough approximation models, namely α-level rough set and β-level rough set, are proposed. It shows that β-level fuzzy rough set model can approximate a fuzzy set at different precisions.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • W. -N. Liu
    • 1
  • JingTao Yao
    • 1
  • Yiyu Yao
    • 1
  1. 1.Department of Computer ScienceUniversity of ReginaReginaCanada

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