Central tendency is a measure of the center of a probability distribution of the-- Central tendency is a measure-- Variance is a measure of how much things change from one observation to another.

集中趋势用以描述,一组概率分布的中心,集中趋势...,而方差衡量的是,各个观察值之间的变化

耶鲁公开课 - 金融市场课程节选

So, there are 2 different things that we can compare when we're comparing graphs of radial probability distribution, and the first thing we can do is think about well, how does the radius change, or the most probable radius change when we're increasing n, when we're increasing the principle quantum number here?

当比较这些径向概率分布图,的时候，我们可以比较两个东西，第一个就是考虑当我们增加ｎ,当我们增加主量子数的时候，半径怎么变，最可能半径怎么变化？

麻省理工公开课 - 化学原理课程节选