Abstract: Based on [P-]set and randomicity of element transfer, the concepts of element transfer probability and internal [Pρ-]set [XPF(f)]are proposed. Moreover, the relationship between internal [P-]set[XF] and internal [Pρ-]set [XPF(f)], and probability characteristics of [XPF(f)] are discussed. The theorems of the relationship between [XPF(f)]and probability of element transfer, unidentification theorem between internal[Pρ-]set family and internal [P-]set family are presented. At the end, their application is given.

Key words: [P-]set, internal [Pρ-]set, element transfer probability

摘要： 在[P-]集合与元素迁移的随机性基础上，给出了元素迁移概率与内[Pρ-]集合[XpF(f)]的概念，讨论了[XPF(f)]与[XF]的关系和内[Pρ-]集合[XPF(f)]的随机特性，得到[XPF(f)]与元素迁移概率关系定理、集合[X]的内[Pρ-]集合族与内[P-]集合族不可辨识定理，最后给出应用。

关键词: [P-]集合, 内[Pρ-]集合, 元素迁移概率