Question

If the sum of squares of differences of ranks for 10 pairs of observations is 66, find the rank correlation coefficient.

Answer 1

Given n = 10,  ∑d² = 66 

We have R = 1 - `[ 6∑d^2 ]/[ n( n^2 - 1 )]`

= 1 - ` [ 6 xx 66 ]/[ 10 ( 10^2 - 1 )]`

= 1 - `396/990` = 1 - 0.4 = 0.6

∴ R = 0.6