Abstract: In the face of complex evaluation problems it requires the joint participation of multiple evaluators, which is termed group evaluation. Normally there are some different evaluation results from different evaluators in the group evaluation process. The differences are composed of evaluators' rational analysis and subjective psychological effect. In which rational analysis as experience or knowledge is objective and difficult to change. Thus, reduce group evaluators' subjective psychological effect results is an important part of rational group evaluation process design. Psychological threshold is an essential component of the subjective psychological effect. It is defined as: psychological qualitative critical point that just can cause feelings or perceived differences in the minimum amount of stimulation. Different evaluators' psychological threshold would lead to some deviations between evaluation result and true value. The psychological threshold differences are produced during the process of evaluators score on evaluated objects' index values or assign weighs according to the degree of importance.
Therefore, a new method of group evaluation is proposed based on psychological threshold synergistic. Firstly, the presumption and process description of psychological threshold group evaluation is described. Secondly, the psychological threshold assignment arithmetic of corresponding efficiency indicator, cost indicator, central indicator and interval indicator is structured. Then the evaluation matrix can be adjusted by the psychological threshold assignment. Thirdly, the psychological threshold assignment of group indicators weighting and the adjustment of indicators weighting matrix are put forward. Finally, the adjustment matrixes are aggregation and the result of the group evaluation which is closer to the real value is gotten. Specific example indicates that the method is effective and feasible. Moreover the evaluation results of traditional and new test methods are not equivalent.
This method has been expanded to the traditional group evaluation. In response to this shortage of traditional method doesn't consider the effect on different psychological threshold, preliminary solutions are presented. The method enables subjective evaluation information from group evaluators achieves a better coordination and unity. The rationality and reliability of the evaluation results can be improved.

Key words: comprehensive evaluation, psychological threshold, subjective assignment, ojective assignment, information aggregation