Abstract: Based on interval two-tuple linguistic information and similarity of vector,a new method was proposed for multiple attribute group decision-making problems with multi-granularity uncertain linguistic information.It hopes to supplement the insufficiency of the method based on distance measure.Firstly,the multi-granularity linguistic information is uniformed using a two-tuple linguistic transformation function.Then,an optimization model,which aims to maximize the similarity degree of the alternatives to the positive ideal solution and minimize that to the negative ideal solution,is established,and then the attribute weights can be determined.The interval two-tuple aggregation operator is utilized to aggregate the linguistic assessment information corresponding to each alternative,and through the optimal ordinal ranking method,the alternatives can be ranked.An example was given to demonstrate the feasibility and efficiency of the proposed method.

Key words: Group decision making,Multi-granularity,Similarity of vector,Interval two-tuple linguistic information,Optimal ordinal ranking