It is difficult to estimate precise probabilities of component states and system states in multistate systems, because of complexity and incompleteness of statistical data.

• 摘要由于多态系统的复杂性、统计数据的不完备等诸多原因，人们往往不能精确地确定系统及其元素的状态概率，也即存在着状态概率表示及计算的不确定性问题。