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转载自：https://blog.youkuaiyun.com/tanzuozhev/article/details/50830928本文摘自Streiner DL.Maintaining standards: differences between the standard deviation and standarderror, and when to use each. Can J Psychi...

经常被这几个名词搞糊涂，为了防止下次继续糊涂，在网上查阅了部分资料，如有不对的地方请指正。方差（variance)：衡量随机变量或一组数据时离散程度的度量。                               概率论中方差用来度量随机变量和其数学期望（即均值）之间的偏离程度。                                统计中的方差（样本方差）是每个样本值与全体...