Core and reduction from mutual relation view and their fuzzy generalization

This paper presents a new rough set model called mutual-relation-based rough set model which is a generalization of Pawlak´s model. Based on the new model, fuzzy core and fuzzy reduction are also proposed. They are the fuzzy generalization of core and reduction of the new model. Two new heuristic algorithms to get reduction of the new model are constructed and illustrated with a simple example.