关键词: 粗糙集, 遗传算法, 适应度函数, 属性约简

Abstract: Attribute reduction is one of the important issues of rough set theory.In order to achieve effectively attribute reduction，a kind of attribute reduction algorithm based on GA is proposed.The conditions attribute is joined relative core according to the importance degree of the condition attribute，and the relative core is joined initial population in GA in order to accelerate convergence.The authors get consequence and decision by using the algorithm to analyze maritime accidences.

Key words: rough set theory, Genetic Algorithms（GA）, fitness function, attribute reduction