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集值信息系统是完备信息系统的广义形式,它当中的一些对象在某些属性下的取值可能不止一个,反映的是信息的不确定性。本文在集值信息系统上引入对象的邻域关系,并以每个对象的邻域作为基本集,建立了集值信息系统的粗糙集方法。为了简化的知识表示,我们进一步讨论了邻域协调集值决策表的正域约简与邻域不协调集值决策表的近似分布约简,给出了正域约简与近似分布约简的等价刻画条件,并借助区分函数给出了计算正域约简与近似分布约简的方法。
Set value information system is a generalized form of a complete information system. Some objects in it may take more than one value under some properties, reflecting the uncertainty of information. In this paper, the neighborhood relations of objects are introduced into the set-valued information system, and the neighborhood of each object is used as the basic set to establish the rough set method of the set-valued information system. In order to simplify the knowledge representation, we further discuss the approximate distribution reduction of the orthonormal reduction and the neighborhood non-coordinated set-valued decision table of the neighborhood coordinated set-valued decision table, and give the reductions of the positive domain reduction and the approximate distribution reduction Equivalent characterization conditions, and with the help of the difference function is given to calculate the reduction of the positive domain and approximate distribution reduction method.