A Simplification of Calculation Method of Attribute Reduction Preserving Lower Approximation Structure in Variable Precision Rough Set Models

Abstract

Variable precision rough set (for short, VPRS) is an extension of Pawlak’s rough set theory to deal with data containing noise or probabilistic information, and various types of reducts are proposed in VPRS. In particular, calculation of reducts preserving lower approximation (called Lβ-reducts) results in calculation of relative reducts of the modified decision tables in Pawlak’s rough set theory. In this paper, we prove that modification of decision tables for computing Lβ-reducts contains redundant procedures.