Question

Determine the Pearson product-moment correlation coefficient for the following data.

x 1 10 9 8 4 3 2

y 10 4 4 5 7 7 9

(Do not round the intermediate values. Round your answer to 3 decimal places.)

Correlation coefficient, r =

Answer 1

Solution:

X	Y	XY	X^2	Y^2
1	10	10	1	100
10	4	40	100	16
9	4	36	81	16
8	5	40	64	25
4	7	28	16	49
3	7	21	9	49
2	9	18	4	81

n	7
sum(XY)	193.00
sum(X)	37.00
sum(Y)	46.00
sum(X^2)	275.00
sum(Y^2)	336.00
Numerator	-351.00
Denominator	362.24
r	-0.9690
r square	0.9389
Xbar(mean)	5.2857
Ybar(mean)	6.5714
SD(X)	3.3375
SD(Y)	2.1148
b	-0.6313
a	9.9083

r = -0.969