A Generalized Deenition of Rough Approximations
نویسنده
چکیده
This paper proposes new deenitions of lower and upper approximations which are basic concepts of rough set theory. These deenitions follow naturally from the concepts of ambiguity and deenability introduced in this paper. The new deenitions are compared to the classical deenitions and are shown to be more general in the sense that they are the only ones which can be used for any type of indiscernibility or similarity relation.
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