I'll make it a capital X. It equals the number of heads I get after 5 flips.

我将其设为大写 ​​X。它等于翻转 5 次后正面朝上的次数。

Or I could have one coin and I could flip it five times and see the number of heads.

或者我可以拿一枚硬币，我可以将它抛五次，看看正面朝上的次数。

When you're adding up random events that's like counting the number of heads.

当您将随机事件相加时，就像计算正面朝上的次数一样。

So the expected value of getting-- the number of heads you get after 6 tosses.

所以得到的期望值-- 抛 6 次后正面朝上的次数。

We just looked at the probability distribution for this random variable, the number of heads after 6 tosses of a fair coin.

我们刚刚查看了这个随机变量的概率分布，即抛 6 次公平硬币后正面朝上的次数。

It's not like, after doing it a thousand times you're like, oh, you can't toss a coin six times anymore and count the number of heads.

这不像，在做了一千次之后你会说，哦，你不能再抛六次硬币然后数正面朝上的次数了。

And we'll do some-- maybe I'll get Excel out and I'll do it where I start saying-- instead of saying, the number of heads in 5 trials.

我们会做一些——也许我会把 Excel 拿出来，我会在我开始说的地方做——而不是说，5 次试验中正面朝上的次数。

We just count the number of heads we got after 5 flips and that's our random variable, X. Let's think a little bit of what are the different probabilities of getting different numbers here?

我们只计算 5 次翻转后正面朝上的次数，这就是我们的随机变量 X。让我们稍微想一想这里得到不同数字的不同概率是多少？

If I did this as the number of heads in 5 million trials, these bars would get very, very close together and you'd start seeing them approach this thing that looks like a bell curve.

如果我在 500 万次试验中将正面朝上的次数这样做，这些条形会非常非常靠近，你会开始看到它们接近这个看起来像钟形曲线的东西。

That if you have a long streak of heads or you have a disproportionate number of heads, that at some point you're going to have-- you have a higher likelihood of having a disproportionate number of tails.

如果你有很长的正面朝上或者你有不成比例的正面，那么在某个时候你会 - 你有更高的可能性有不成比例的尾巴。

The law of large numbers will just tell us that-- let's say I have a random variable-- X is equal to the number of heads after 100 tosses of a fair coin-- tosses or flips of a fair coin.

大数定律只会告诉我们——假设我有一个随机变量——X 等于抛硬币 100 次后正面朝上的次数——抛硬币或抛硬币。