The Karl Pearson’s correlation coefficient (r) between two random variables, X and Y, is computed by:
1
r(X,Y) = Cov(X,Y)*σXσY
2
\(\rm r(X,Y)=\frac{\sigma_X \sigma _Y}{Cov(X,Y)}\)
3
\(\rm r(X,Y)=\frac{Cov(X,Y)}{\sigma_X \sigma _Y}\)
4
\(\rm r(X,Y)=\frac{Cov(X,Y)}{(\sigma_X \sigma _Y)^2}\)