One person might be a little low one day, another person might be high, a lot of people might-- you might happen to have captured them on an average day, but overall it averages out, so you get a representative sample.

一个人可能某一天少吃些,另一个人可能多吃些,很多人都会这样,你可能正好得出人们,平均每天的摄入量,但把它的整体平均一下,就得到有代表性的结果

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

This is very important,which is why I am doing it: "If we want to know how fast a human being can run, then it is no use to average out the speed of a "good sample" of the population; it is far better to collect Olympic gold medal winners and see how well they can do.

这话非常重要，是我作这个研究的原因：,“如果想知道人类最快能跑多快，那从好的样本中测出平均数是“,没用的;,而应该收集田径类奥运冠军的信息,看他们能跑多快。

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