We can define it in a couple of different ways depending on whether we're talking about sample mean or population mean.

我们有几种不同的方式去定义这个概念,取决于我们指的是,样本均值还是总体均值

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That means--his calculations are very different than the ones I have because he has a much longer sample period.

那表明。。。他的计算结果与我的大相径庭,因为它数据的取样跨度比我的长多了。

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