集值信息系统下基于λ-近似的属性相对约简

Attribute Relative Reduction of Set-valued Information Systems Based on λ-Approximations

针对集值信息系统,基于相容关系下的极大相容类及OWA算子的性质,提出了λ-近似算子,给出了λ-近似算子下的λ-上、下近似集合,并分析了λ-近似算子的性质。同时,借鉴基于属性重要度的启发式约简算法,通过模糊化λ-下近似集合,进一步得到了属性的相对依赖度及属性的相对约简。

In this paper,the definition on approximation operators associated with λ is proposed in set-valued information systems,based on the maximal tolerance classes of tolerance relation and properties of OWA operator,from which λupper and λ-lower approximation sets are given.And the properties of λ-approximation operators is discussed.Further,by fuzzed of λ-lower approximation sets and the concept of heuristic algorithm on attribute significance,attributes relative dependency degree and attribute relative reduction would be provided.