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多尺度信息系统是一种特殊的信息系统,其属性的取值存在多个尺度.现有的研究只讨论了每个对象在一个属性的各个尺度上取一个值的信息系统.但是,在一些实际的数据集中,对象的属性值可能不限于单个值,而是多个值,即集值.为此,文章提出了多尺度集值信息系统的概念.然后,定义了多尺度集值信息系统中对象的相似关系,研究了不同尺度下的粗糙近似及其相关性质.在多尺度集值决策系统中,给出了广义决策、上近似分布、下近似分布和正域的定义,并提出了相应的最优尺度判定准则.最后,从一致性和不一致性的角度分析了不同准则下的最优尺度之间的关系.“,”The multi-scale information system is often studied as a special information system.The existing researches only discuss the information system that each object only takes a single value at all scales of an attribute.However,in some real-world data sets,the attribute value of an object is not limited to a single-value,but may take multiple values,namely a set-value.We propose the concept of multi-scale set-valued information system.The rough approximation at different scales and its related properties can be obtained via the similarity relation between objects in a multi-scale set-valued information system.In addition,the definition of optimal scale is proposed based on the generalized decision,upper approximation distribution,lower approximation distribution,and positive region in a multi-scale set-valued decision system.The rela-tionships among these optimal scales based on different criterions are further analyzed from the perspec-tives of consistency and inconsistency.