Question

 If `Σd_i^2` = 25, n = 6 find rank correlation coefficient where d_i, is the difference between the ranks of i^th values.

Answer 1

Here given `∑di^2=25`   

           n = 6 

The rank correlation coefficient is given by 

`r=1-(6∑di^2)/(n(n^2-1))` 

=`1-(6xx25)/(6(36-1))` 

=`1- 150/(6xx35)`

=`1- 150/(210)`

= `1 -5/7` 

`r=2/7`

= 0.2857