Lower and Upper Approximations in Hv- groups

B. Davvaz


The purpose of this paper is to introduce and discuss the concept of lower and upper approximations. A simple and straightforward way for interpreting rough sets is to use membership functions. We investi-gate the similarity between rough membership function and conditional probability. We also consider the fundamental relation kr defined on an Hy-group H and interprets the lower and upper approximations as sub-sets of the group Hi/` and give some properties of such subsets.


Hypergroup; Hy-group; Fundamental group; Interval set; Rough set; Lower and upper approximations; Conditional probability.

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