Abstract: Rough set method weights the attributes according to the significance degree,which overcome the shortage of common weighting methods that overly relied on the expert's transcendental knowledge. But the autologous improtance of the attributes may always be neglected.In this paper,Analytic Hierarchy Process(AHP)is used together with rough set weighting method to put forward a new combination weighting method based on maximizing deviation principle.This new combination weighting method may integrate the merits of both subjective and impersonal weightiing methods,maximizing deviation improves the traditional combination weighting method,and may lead to a more reasonal weighting result and easy decision.Finally,an applied example proves the feasibility of the new combination weighting method.

Key words: rough set, analytic hierarchy process, combination weighting, maximizing deviations