ALGORITHMS FINDING REDUCTIONS FOR A SINGLE AND A SET-VALUE INFORMATION SYSTEM USING THE CONCEPT OF POSITIVE REGION
This paper studies some concepts and properties of positive region of Pawlak’s rough set. Consequently, we propose some constraints among attributes, especially among conditional attributes which are in decision systems. We then introduce algorithms to find the reductions for both a single and a set-value information system. Furthermore, we will prove that in the proposed algorithm a set-value information system can be considered as a single information system.