Optimistic multi-granulation fuzzy rough set model in ordered information system

With granular computing point of view, the classical dominance based rough set model is based on a single granulation. On the basis of the analysis of rough set model over a dominance relation and the theory of fuzzy rough set, a new generalized rough set model over dominance relations is constructed, which is optimistic multi-granulation fuzzy rough set model over dominance relations. It follows the research on the properties of the lower and upper approximations of the optimistic multi-granulation fuzzy rough set model over dominance relations. The fuzzy rough set model and classical rough set model on a dominance relation are special cases of the new one from the perspective of the considered concept and granular computing.