Special Features of Rank Correlation

The special features of Spearman’s rank co-efficient of correlation can be outlined as under:

• The value of such co-efficient of correlation les between +1 and -1.
• The sum of the differences between the corresponding ranks i.e.  ∑d=0.
• It is independent of the nature of distribution from which the sample data are collected for calculation of the co-efficient.
• It is calculation on the basis of the ranks of the individual items rather than their actual values.
• Its result equals with the result of Karl Pearson’s co-efficient of correlation unless there is repletion of any rank. This is because, Spearman’s correlation is nothing more than the Pearson’s co-efficient of correlation between the ranks.