CA Foundation P3 · Chapter 17 · Question 4 of 9
For 6 pairs of ranks, the sum of squares of rank differences Σd² = 14. Spearman's rank correlation coefficient is (to two decimals):
Test yourself: pick an answer
Reveal answer & explanation
Correct answer: D) 0.60
Explanation
R = 1 − 6Σd²/[n(n² − 1)] = 1 − (6 x 14)/(6 x 35) = 1 − 84/210 = 1 − 0.40 = 0.60. Omitting the factor 6 in the numerator gives 1 − 14/210 = 0.93, 0.40 forgets to subtract from 1, and −0.60 has the wrong sign.
More Correlation and Regression MCQs
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