An Extension of the Fuzzy DEMATEL Method for Group Decision Making

The Fuzzy Decision Making Trial and Evaluation Laboratory (Fuzzy DEMATEL) method is one of the Multi Criteria Decision Making tools, which can structure complex problems through visual structural model and analyze the causal relationship between factors. In the existing literature, the Fuzzy DEMATEL method assumes that all the decision makers are equal in their relative weights of importance in the problem considered. However, in some complex group decision making problems this has its drawbacks. This paper proposes a fuzzy DEMATEL method for group decision-making with non-equal importance weights of individual members in the group. The directed influential degrees between pair-wise factors are expressed as fuzzy numbers in order to model the uncertainty and imprecision judgments from the group’s members. Unlike the known Fuzzy DEMATEL, the proposed method considers the importance weights of individual members in the group and presents those weights as either crisp numbers or fuzzy numbers, which are used in a fuzzy aggregation procedure. In this procedure, the Weighted Arithmetic Mean method is applied for individual members’ weights of importance, represented as crisp values, whereas, the Fuzzy Weighted Arithmetic Mean method is used for the fuzzy weights. For assisting decision makers to apply the proposed method, a prototype of a decision support tool is developed using the MATLAB Software. A comparison between the proposed and the traditional Fuzzy DEMATEL methods is illustrated with a numerical example. The results show that the proposed method is more suitable and reasonable than the traditional Fuzzy DEMATEL method.