Ranking members of sets with uncertain center by using general type-2 fuzzy membership values

Abstract

In this paper a new method is proposed for ranking members of the set with uncertainty in the center of set. It means that the set's center is considered as multi objects rather that single object. The degree of belonging to the set is defined based on general type-2 fuzzy membership values which the primary variable indicates the closeness to the each center; and the secondary variable indicates the center position compared to other central objects in the set. Then, the centroid approached is applied for ranking the general type-2 membership values. The performance of the model is demonstrated by applying on a numerical example and results are compared with ranking list based on type-1 fuzzy membership values.