基于焦元距离的冲突证据组合规则

Combination rule of conflicting evidence based on focal element distance

由于Dempster-Shafer理论(Dempster-Shafer theory,DST)组合规则归一化计算导致冲突信息的不合理分配,使得处理高冲突证据时常常得到违背直觉的合成结果,因此在很大程度上制约了它的应用。提出了一种基于焦元距离的冲突证据组合规则,首先通过定义焦元距离的概念来获得证据源的权重因子,并引入了焦元置信指派的数学期望和方差关系来定义证据焦元的信任度和相似度,通过分析局部冲突产生的原因,利用冲突焦元提供的信息将冲突信息进行局部分配。实验结果表明,新的组合规则不但可以有效地解决高冲突证据融合问题,而且在最差的融合顺序下也能得到合理的融合结果。

The normalization calculation of Dempster-Shafer theory（DST） combination rule results in the irrational distribution of conflicting information,which often makes the counterintuitive results in the highly conflicting information fusion and restricts its application.The combination rule of conflict evidence based on the focal element distance is proposed.Firstly,the weight factors of the evidence source are obtained based on the focal element distance of the evidence source.Then the credibility and similarity degree of the focal element is defined by the relation of mathematical expectation and variance.After analysing the cause leading to a local conflict,the conflicting informations are distributed exploiting the data provided by the focal elements in conflicting evidence.The results of numerical examples prove that the new combination rule can not only effectively solve the combination of highly conflicting evidence but also obtain the reasonable results in the worst combination sequence.