Question

Compute the correlation? coefficient

x	1	5	7	7	9
y	1.2	1.9	1.9	2.0	2.6

Answer 1

Solution:

x y xy x^{2   y2}  

1 1.2 1.2 1 1.44

5 1.9 9.5 25 3.61

7 1..9 13.3 49 3.61

7 2.0 14.0 49 4

9 2.6 23.4 81 6.76

29 9.6 61.4 205 19.42

r = n ( xy )- (x ) (y) / n [ ( x² ) - ( x )² ] [ n (y² ) - ( y )²

^{r = 5 (61.4 ) - (61.4 * 29)} /    [ 5 * 205 - ( 29 ) ²   [ 5 * 19.42 - ( 9.6 ) ² ]

=307-278.4?1025-841??97.1-92.16

=28.6?184??4.94

=28.613.5647?2.2226

=28.630.149

=0.9486

The correlation? coefficient = 0.9486