rowSkew

New in version 1.30.14.

语法

rowSkew(X, [biased=true])

row 系列函数通用参数说明和计算规则请参考: 行计算系列(row 系列)

参数

biased 是一个布尔值,表示是否为有偏估计。默认值为 true,表示为有偏估计。

详情

逐行计算 X 的斜度。

DolphinDB 使用以下公式计算倾斜度(当 biased=true 时):

\(skew(x)=\dfrac{\dfrac{1}{n} {\sum\limits_{i = 1}^{n} (x_i - \bar{x})^3}} {\left(\sqrt{\dfrac{1}{n} {\sum\limits_{i = 1}^{n} (x_i - \bar{x})^2}}\right)^3}\)

例子

$ m = [4.5 2.6 1.5 1.5 4.8, 5.9 4.9 2.0 4.0 6.3, 2 2 2 2 2]
$ rowSkew(m);
[-0.329206341655613,0.586870565935934,-0.707106781186563,0.595170064139497,-0.350377619697706]

$ m=matrix([4.5 2.6 1.5, 1.5 4.8 5.9, 4.9 2.0 NULL, 4.3 NULL 3.5]);
$ rowSkew(m);
[-1.064430070205901,0.577633692366209,0.110780117654846]

$ t1=table(1..5 as x, 10..6 as y, take(3, 5) as z);
$ rowSkew(t1);
[0.567316577993729,0.652012117044047,0.707106781186548,0.528004979218188,-0.381801774160629]

相关函数: skew