Multiple stages grey target decision making method with incomplete weight based on multi-granularity linguistic label

The method of grey target decision making based on a multiple stages linguistic label is extended in this research. Firstly, the multi-granularity linguistic term sets are transformed into the same linguistic set. Next, the choice rule of a target is put forward and the calculation of a target distance is developed. Furthermore, weight models of criteria and of stages, which are based on the requirement of maximum difference of alternatives and restriction of stage harmony, are suggested. In addition, a model of lower and upper value of a target distance is put forward. Moreover, the method is extended to the group decision making environment. This model can help to avoid faulty decision making due to uncertainty. The suggested method is applied to vendor evaluation of a commercial airplane in China.