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方差用什么表示

更新时间: 2020-10-04 00:00:00     

方差是在概率论和统计方差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,统计中的方差是每个样本值与全体样本值的平均数之差的平方值的平均数。

方差符号为s的平方

关键词: 什么 表示

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