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

耶鲁公开课 - 金融市场课程节选

One is in the U.S.at the Centers for Disease Control, where there is a sample of variola, which is kept, you know, frozen on ice in a heavily guarded facility.

一个在美国的疾病控制中心,那有一支天花病毒的样本,冰冻后置于重重保护之下

耶鲁公开课 - 生物医学工程探索课程节选

And I say if you took a random sample of the Americans: "When you woke up in the middle of the night" and said: "What does the America stand for?"

我觉得如果给美国人做个抽样调查：,半夜醒来的时候“,被问到，美国人主张什么“

普林斯顿公开课 - 国际座谈会课程节选

Well let's talk about some mechanisms for using this and I'll start with a simple example of how one can detect a gene in a fluid, in a blood sample for example, where that gene is unknown.

我们来说说这项技术在实际应用中的机制,先从一个简单例子着手,如何在一个血样中,侦测是否存在某段基因序列,某段未知基因序列

耶鲁公开课 - 生物医学工程探索课程节选