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标准差计算方式

更新时间: 2021-05-04 22:21:42     

1、标准差公式是一种数学公式。标准差也被称为标准偏差,或者实验标准差,公式如下所示:

2、样本标准差=方差的算术平方根=s=sqrt(((x1-x)^2 +(x2-x)^2 +......(xn-x)^2)/(n-1))

3、总体标准差=σ=sqrt(((x1-x)^2 +(x2-x)^2 +......(xn-x)^2)/n )

4、注解:上述两个标准差公式里的x为一组数(n个数据)的算术平均值。当所有数(个数为n)概率性地出现时(对应的n个概率数值和为1),则x为该组数的数学期望。

关键词: 标准 计算 方式

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