That's different when you have continuous values-- you don't have P because it's always zero.

和离散型随机变量的分布不同的是,连续型随机变量的分布中,某一点的概率值始终是零

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You have discrete random variables, like the one I just defined, or there are also--which take on only a finite number of values-- and we have continuous random variables that can take on any number of values along a continuum.

就像刚定义的,是一个离散型随机变量,随机变量还可以有无限种取值,也就是连续型随机变量,随机变量可以取某一区间的一切值

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