基于pignistic概率距离的改进证据组合规则

针对使用传统冲突系数识别证据冲突存在的不足，采用pignistic变换后得到的概率赋值函数之间的距离，结合传统冲突量化标准，讨论了Dempster组合规则适用条件，并提出了一种改进的证据组合方法.该方法通过证据之间的pignistic概率距离表示证据之间的冲突程度，将证据间的冲突程度转化成相似程度，然后求出证据之间的支持程度，并确定权重系数，最后采用Dempster组合规则合成权重系数调整后的基本概率赋值.数值算例分析结果表明，改进的证据组合方法可以有效地处理证据冲突，且具有较快的收敛速度.

Improved Combination Rule of Evidence Based on Pignistic Probability Distance

To remedy the shortcomings in the recognition of evidence conflict by using conventional conflict coefficient, this paper discussed the application conditions of Dempster’s combination rule by traditional conflict quantification standard and the distance among probability assignment functions transformed by pignistic. Furthermore, the paper presented an improved method of evidence combination. In this method, the conflict level is represented by the pignistic probability distance of evidence, after that the conflict level is transformed into similarity level and the support degree of evidence is obtained. In addition, the weight coefficients are determined. Finally, the basic probability assignments adjusted by weight coefficient are fused by Dempster’s combination rule. The numerical examples prove that the modified method can resolve the evidence conflict efficiently and has fast convergence speed.