Correct Answer - Option 1 : -0.3
Calculation
The coefficient of rank correlation = 1 – 6∑d2/n(n2 – 1)
D = r1 – r2
r1, r2 ------ are ranks
Mathematics (r1)
|
Statistics (r2)
|
d = Ir1 – r2I
|
d2
|
3
|
6
|
3
|
9
|
5
|
4
|
1
|
1
|
8
|
9
|
1
|
1
|
4
|
8
|
4
|
16
|
7
|
1
|
6
|
36
|
10
|
2
|
8
|
84
|
2
|
3
|
1
|
1
|
1
|
10
|
9
|
81
|
6
|
5
|
1
|
1
|
9
|
7
|
2
|
4
|
Total
|
10
|
|
∑d2 = 214
|
According to spearman’s rank correlation coefficient ρ = 1 – 6∑d2/n(n2 – 1)
⇒ 1 – 6 × 214/10(100 – 1)
⇒ 1 – 6 × 214/990
⇒ 1 – 1.297
∴ The value of rank correlation is approx. – 0.3