Abstract: The existing approaches aren't able to solve the decision problems that evidence sourses are subjective or objective evidence sourses that can't obtain efficient information, and thus we have to look for help from subjecitve knowledge, experience and intuition. In order to solve above problems, the flexible knowledge matrice given by relative estimation modes with complementary judgments are established to derive subjective inference information from decision experts, and a subjective evidence deriving model is constructed to obtain Basic Probability Assignment (BPA) functions from flexible knowledge matrice. After that, four priciples in Brain Storming, i.e., delayed evaluation, independently thinking, quality ensured by quanity, as well as combined to improvment, are introduced to the procedure of deriving subjective evidences, and a integrating and decision making method is proposed to recognize the most possible alternative in the frame of discernment. A numerical comparison analysis and a case simulation analysis are respectively presented to demonstrate the proposed method to be scientific, efficient, and feasible finally.

Key words: subjective evidence, dempster-shafer evidence theory, brain storming, decision making method, group decision making