In computer science, a rough set, first described by a Polish computer scientist Zdzisław I. Pawlak, is a formal approximation of a crisp set (i.e., conventional set) in terms of a pair of sets which give the lower and the upper approximation of the original set. In the standard version of rough set theory (Pawlak 1991), the lower- and upper-approximation sets are crisp sets, but in other variations, the approximating sets may be fuzzy sets.
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Famous quotes containing the words rough and/or set:
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—Gil Doud, U.S. screenwriter, and Jessie Hibbs. Johnson (Marshall Thompson)
“I concluded that I was skilled, however poorly, at only one thing: marriage. And so I set about the business of selling myself and two children to some unsuspecting man who might think me a desirable second-hand mate, a man of good means and disposition willing to support another man’s children in some semblance of the style to which they were accustomed. My heart was not in the chase, but I was tired and there was no alternative. I could not afford freedom.”
—Barbara Howar (b. 1934)