Evaluation and Selection of Sustainable Suppliers by Using a Mix of MCDM Techniques and Utilizing Taguchi Loss Function in Determination of Final Scores

In today's competitive world, supply management plays a significant role in achieving an efficient supply chain. One of the most important goals of supply management is to select sustainable suppliers and determine the optimal order allocated to suppliers. The process of selecting a sustainable supply begins with the determination of the criteria which are effective on the decision. Considering that the importance of all these criteria is not the same for organizations, multi-criteria decision-making methods are used to determine the weights of these critera. In this paper, three methods of Fuzzy DEMATEL, combination of analytical network process method and fuzzy DEMATEL type 1 and combination of analytic network process method and Fuzzy DEMATEL type 2 are used to determine the weights of effective criteria. Also, to determine the scores of suppliers, the innovative combined approach of fuzzy Taguchi loss function and fuzzy method of similarity to the ideal solution is used. In the hybrid approach, first, experts give scores to suppliers for their performance in different political, economic, social conditions, and based on this, the fuzzy Taguchi loss function is calculated. Considering that the loss function has a negative charge, the Taguchi loss functions are inverted and used as the input of the fuzzy TOPSIS method. In this paper, the sensitivity of the mentioned multi-criteria decision-making methods in calculating the weights of the criteria is examined with different conditions. The scores of suppliers are calculated based on their performances in the worst, normal and best conditions.