Fuzzy Rough Sets: from Theory into Practice
نویسندگان
چکیده
Fuzzy sets and rough sets address two important, and mutually orthogonal, characteristics of imperfect data and knowledge: while the former allow that objects belong to a set or relation to a given degree, the latter provide approximations of concepts in the presence of incomplete information. In this chapter, we demonstrate how these notions can be combined into a hybrid theory that is able to capture the best of different worlds. In particular, we review various alternatives for defining lower and upper approximations of a fuzzy set under a fuzzy relation, and also explore their application in query refinement.
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