A Grey-Based Rough Set Approach to Suppliers Selection Problem

Abstract

The suppliers selection problem is one of the most important components in supply chain management. In recent years, rough set theory has emerged as a powerful tool for suppliers selection problem. In this paper, we proposed a grey-based rough set approach to resolve suppliers selection problem. The work is motivated by the following observations: First, in the decision table of rough set theory, attribute values must be known precisely. Generally, decision makers’ judgments on attribute often cannot be estimated by the exact numerical value. Second, in rough set theory, the alternatives of ideal suppliers are decided by lower approximation, so the ranks of each ideal supplier is equal. Therefore it is difficult to select the best ideal supplier. The work procedure is shown as follows briefly: First, the attribute values of rough set decision table for all alternatives are decided by linguistic variables that can be expressed in grey number. Second, ideal suppliers are decided by the lower approximation of grey-based rough set theory. Third, the best ideal supplier is decided by grey relational analysis based on grey number. Finally, an example of selection problem of suppliers was used to illustrate the proposed approach.