A Fuzzy Best-Worst Multi-Criteria Group Decision-Making Method

This paper proposed a novel fuzzy best-worst multi-criteria group decision-making method to solve the group decision-making (GDM) problem with multi-granular linguistic approach, which is an effective and promising technique to tackle this issue. In the proposed method, the selectable multi-granularity linguistic term sets (LTS) are firstly provided for experts to expressed their individual assessment information. Then, the improved fuzzy BWM is employed to calculate the weights of criteria with the form of fuzzy numbers. In current several studies using the BWM for group decision-making, only two unified best and worst criteria are given, which cannot reflect the evaluation of the best and worst criteria by different experts, resulting in the omission of information. Moreover, the difference between the best and worst criteria initially given and the experts' ideas will cause the experts to be inaccurate in the comparison of each criterion. Therefore, in this paper, in order not to omit too much information, each expert will determine the best and the worst criteria. The evaluation information of each expert is integrated into two comparison vectors according to the transformation formula proposed in this paper. What's more, an improved input-based consistency measurement is proposed, which can provide the DMs with a clear guideline on the revision of the inconsistent judgement(s). Finally, two examples are given to illustrate the effectiveness and applicability of the proposed method.