Illustration of Rank Correlation Coefficient

In a beauty competition two assessors were asked to rank the 10 contestants by using the professional assessment skills. The results obtained were described as shown in the table below as:

REQUIRED

Compute the rank correlation coefficient and thus comment briefly on the value acquired

∴ The rank correlation coefficient R

R = 1 -  {(6Σd²)/(n(n² -1))}

= 1 -  {(6(36))/(10(10² -1))}

= 1 -  (216/990)

= 1 - 0.22

= 0.78

Comment: because the correlation is 0.78 it implies that there is high positive correlation among the ranks awarded to the contestants. 0.78 > 0 and 0.78 > 0.5.