Spearman's coefficient of correlation - class-XI

$1-\dfrac{6\sum D^2}{n(n^2-1)}$

$\dfrac{1}{n}\sum(x-\overline x)(y-\overline y)$

$\dfrac{\dfrac{1}{n}\sum(x-\overline x)(y-\overline y)}{\sigma _x\sigma _y}$

$1-\dfrac{6[\sum D^2+\dfrac{1}{12}(m _1^3-m _1)+frac{1}{12}(m-2^3-m _2)+....]}{n(n^2-1)}$