Disjunctive set-valued ordered information systems based on variable precision dominance relation

Abstract

Through analyzing limitations of four existing dominance relations in disjunctive set-valued information systems, a variable precision dominance relation is proposed, and an extended rough set model based on the variable precision dominance relation is defined. In order to derive much simpler attribute representation, a discernibility matrix is defined, and an attribute reduction method based on the discernibility matrix is developed. © 2011 Springer-Verlag.