Causality diagram theory is an uncertainty reasoning methodology based on probability theory, it can progress dynamic reasoning online and fault diagnosis to complex system, but the probability is precision value in causality diagram.

• 摘要因果图理论是一种基于概率论的不确定推理模型，能够进行在线动态推理和对复杂系统进行故障诊断，但在因果图模型中，要求事件的发生概率为精确值。