A KNOWLEDGE REDUCTION METHOD BASED ON TOLERANCE ROUGH SET THEORY IN KDD

In order to overcome the shortcoming of general rough set theory, the elementary concept of tolerance rough set theory is proposed in this paper, and is used to build objects’ tolerance relations that can correctly classify objects in system. We use genetic algorithms to search for the optimal thresholds, then construct special matrix for attributes and objects. We can get the relations among attributes, objects and relative absorbent set of objects in detail. The method of using tolerance rough sets reduces the qualitative processing and improves the validness of knowledge reduction. Finally, we present examples, illustrating our approach in the paper.