关键词: 粗糙集理论, 属性约简, 启发式算法, 医疗诊断

Abstract: The attribute reduction algorithm based on the core of distinct matrix always has poor efficiency in both time and space.A novel heuristic algorithm is proposed for attribute reduction based on rough set theory.Distinct matrix is not constructed and stored directly and a better core set can be obtained even if the core element is not existent.Obtaining the matrix element and core element are carried out simultaneously and the frequency of attribute set is considered in this method.Then the method is applied to medical diagnostic decision-making.Experiment results show that by using the reduced attribute set，it not only can decrease the computational complexity but also can keep high decision accuracy.The algorithm can find a good attribute subset.

Key words: rough set theory, attribute reduction, heuristic algorithm, medical diagnosis