A Construction of Hierarchical Rough Set Approximations in Information Systems Using Dependency of Attributes
نویسندگان
چکیده
This paper presents an alternative approach for constructing a hierarchical rough set approximation in an information system. It is based on the notion of dependency of attributes. The proposed approach is started with the notion of a nested sequence of indiscernibility relations that can be defined from the dependency of attributes. With this notion, a nested rough set approximation can be easily constructed. Then, the notion of a nested rough set approximation is used for constructing a hierarchical rough set approximation. Lastly, applications of a hierarchical rough set approximation for data classification and capturing maximal association in document collection through information systems are presented.
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