And that's how you do it for an expected value of a random variable.

这就是你如何为随机变量的期望值做的。

And in this video, I'm going to introduce you to the concept of the expected value of a random variable.

在本视频中，我将向您介绍随机变量期望值的概念。

So the expected value of a random variable, the expected value of a random variable is the exact same thing as the population mean.

因此，随机变量的期望值，随机变量的期望值与总体均值完全相同。

Now we know that the expected value, the way you calculate an expected value of a random variable is you just take the probability weighted sum.

现在我们知道期望值，计算随机变量期望值的方法就是取概率加权和。

The binomial distribution tells us that the expected value of a random variable is equal to the number of trials that that random variable's kind of composed of, right?

二项分布告诉我们，随机变量的期望值等于该随机变量组成的试验次数，对吗？