基于k等价度容差关系的变精度粗糙集模型及其约简算法

针对k等价度容差关系，提出了一种基于k等价度容差关系的变精度粗糙集模型，该模型是变精度粗糙集模型在不完备信息系统中的拓展．在此基础上，定义了变精度粗糙集模型约简的概念，讨论了一种刻画属性重要性的新指标，提出了一种启发式约简算法．该算法能从搜索空间中不断地添加重要的属性，并且删除不重要的属性，从而降低了约简的时间复杂度．最后，通过实例说明该算法的有效性．

Variable Precision Rough Set Model and Attribute Reduction based on k -equivalent Degree Tolerance Relation

Variable precision rough set model based on k -equivalent degree tolerance relation is pro- posed in this paper, and it is a spread that variable precision rough set model in incomplete information sys- tem. Attribute Reduction is defined in variable precision rough set, and a new index for measuring signifi- cance of the attributes of variable precision rough set is also presented. Then, a heuristic reduction algorithm for variable precision rough set based on k -equivalent degree tolerance relation is proposed. The proposed al- gorithm is of less time complexity since it adopts the strategy of removing unimportant attributes and in- creasing relative important attributes from the search space. Finally, a real example is used to demonstrate the effectiveness of the proposed algorithm.