A Flexible Decision-Making Method for Green Supplier Selection Integrating TOPSIS and GRA Under the Single-Valued Neutrosophic Environment

The deteriorating environment and growing environmental awareness have created an urgency for selecting green suppliers. Although scholars have put forward many methods for selecting an appropriate green supplier, most of the existing methods are based on the fixed weight system, which causes these methods to fail to cope with complex and dynamic decision-making environment. To solve this problem, we develop a flexible decision model for green supplier selection where entropy, Technique for order preference by similarity to ideal solution (TOPSIS), and grey relational analysis (GRA) are embedded in the single-valued neutrosophic environment. The single-valued neutrosophic set is a superior tool in dealing with uncertainties, while the integration of single-valued set and classic methods for green supplier selection is limited. In this paper, entropy is integrated with the single-valued neutrosophic set to determine the weights of the criteria for green supplier evaluation; the weighted distance of TOPSIS and the weighted similarity of GRA are combined to select the optimal green supplier. The weights of TOPSIS and GRA are flexible; variable weights are assigned to TOPSIS and GRA based on different decision-making environments. A case study, along with comparative analysis, is carried out to prove the availability of our proposed decision model. Results show that our proposed decision model is flexible to accommodate dynamic decision-making issues and has good practicality.