Question

The value of Spearman's rank correlation coefficient of a set of non-repeating values was found to be 2/3. The sum of the squares of difference between the corresponding ranks was 55. Find the number of pairs.

Answer 1

$\rho=1-\frac{6\Sigma d_i^2}{n(n^2-1)}$

$\frac{2}{3}=1-\frac{6*55}{n(n^2-1)}$

$n(n^2-1)=990$

n=10