If you have an experiment and the outcome of the experiment is a number, then a random variable is the number that comes from the experiment.

如果你有一个试验,这个试验的结果是一个数,那么相对应的随机变量,指的就是这个试验结果所对应的那个数

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For example, the experiment could be tossing a coin, I will call the outcome heads the number one, and I'll call the outcome tails the number zero, so I've just defined a random variable.

比方说,抛硬币的试验,我将正面向上的结果对应数字1,反面向上的结果对应数字0,这样我就定义了一个随机变量

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I have it down that there might be an infinite number of possible values for the random variable x.

对于这个随机变量X,可能的取值个数是无限的

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The basic definition-- the expected value of some random variable x--E--I guess I should have said that a random variable is a quantity that takes on value.

最基本的定义,某一个随机变量X的期望值E,我应该提到过,随机变量是一个可以取值的数

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