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Answers to questions

Question 5

Spearman's rank correlation

Calculate Spearman’s rank correlation coefficient for the following data.

rank set 1 rank set 2
5 6
1 2
3 4
6 5
2 1
4 3

6∑d 2
R = 1 -
2
n(n –1)
2
rank set 1 rank set 2 d d
5 6 –1 1
1 2 –1 1
3 4 –1 1
6 5 1 1
2 1 1 1
4 3 1 1

∑d 2 6
R = 1 – (6 × 6)/[6 × (36 – 1)]

R = 1 – 36/210 = 0.83

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