So that's my probability distribution function. If I were to draw a mean, this is symmetric, so maybe the mean would be something like that. It would be halfway, so that would be my mean right there, the standard deviation. Maybe it would be that far and that far above and below the mean. But that's my discrete probability distribution function. Now what I'm going to do here, instead of just taking samples of this random variable that's described by this probability distribution function, I'm going to take samples of it, but I'm going to average the samples, and then look at those samples and see the frequency of the averages that I get. And when I say average, I mean the mean.