负二项分布的两个不同定义

摘要

给出了负二项分布的两个不同定义，给出了两类负二项随机变量的期望、方差与矩母函数。从直观上对这两类负二项随机变量做了描述。%Two definitions of the nega tive binomial distributions are introduced. The expectations, variances and moment generating functions for two types of the negative binomial random variables are computed. Intuitive and descriptive explanations are made for the negative binomial random variables.