D-S证据理论中冲突证据的合成方法

针对高度冲突证据的合成问题,分析了D-S合成方法及其改进方法的不足,提出了一种新的改进方法。新方法仍利用D-S合成公式,但针对该公式要求参与合成的各证据需具有相同重要程度的要求,考虑到融合系统中各证据的重要程度可能不同,直接利用公式合成可能得到与实际相悖的结论,因而引入证据权的概念,给出了证据权的具体算法,通过证据权对已有的基本可信度分配函数进行修正得到了重要性相同的新的证据的基本可信度分配模型。最后通过算例比较表明新方法的合成结果更为理想。

Combination of Conflict Evidences in D-S Theory

D-S combination rule and other modified methods are defective in resolving evidence combination problem of highly conflict evidences. So we propose a new modified method. The new method still uses the D-S combination rule. All evidences must have the same important degree when they are combined with D-S combination rule. In practice, evidences may have different important degree so we maybe get paradoxical result if we directly combine these evidences. Therefore we introduce a concept of evidence weight and give the concrete algorithm for the evidence weight. Then new evidences with the same evidence weight can be got by modifying the basic belief assignment function of primary evidences through the algorithm to the evidence weight. Finally, an example indicates that the new method can give the more reasonable combination results compared with D-S combination rule and the other modified methods.