Iron and steel companies green suppliers' selection model based on Vague sets group decision-making method

Iron and steel enterprises green suppliers' selection belongs to a fuzzy multi-criteria decision problem. Vague sets method is suitable for solving the problems of this kind. However, the score function and the similarity calculation method of Vague sets still have some defects so that cannot reflect the experts' opinion precisely. This paper proposed new methods based on limit formula to calculate the score function and similarity of Vague sets. A case of green suppliers' selection verified the advantage of this method.