# GeoDesign Knowledge Portal

## Fuzzy Set

Fuzzy sets are sets whose elements have degrees of membership. Fuzzy sets were introduced by Lotfi A. Zadeh (1965) as an extension of the classical notion of set. In classical set theory, the membership of elements in a set is assessed in binary terms according to a bivalent condition — an element either belongs or does not belong to the set. By contrast, fuzzy set theory permits a graduated assignment of the membership of elements in a set. This is described with the aid of a membership function valued in the real unit interval [0, 1]. Fuzzy sets generalize classical sets, because the indicator functions of classical sets are special cases of the membership functions of fuzzy sets, if the latter only take values 0 or 1.

Data Attributes

Keith Reynolds

6/5/2008

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