Reduction Algorithms Based on Discernibility Matrix: the Ordered Attributes Method

摘要

In this paper, we present reduction algorithms based on the principle of Skowron's discenibility matrix-the ordered attributes method. The completeness of the Algorithms for Pawlak reduct and the uniqueness for a given order of the attributes are proved. Since a discernibility matrix requires the size of the memory of |U|~2, U is a universe of objects, It would be impossible to apply these algorithms directly to a massive object set. In order Ro solve the problem, a so-called quasi-discernibility matrix and two reduction algorithms are Proposed.