Question

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

x 1 11 9 6 4 3 2

y 10 4 5 5 7 7 8

(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
11	4	44	121	16
9	5	45	81	25
6	5	30	36	25
4	7	28	16	49
3	7	21	9	49
2	8	16	4	64

n	7
sum(XY)	194.00
sum(X)	36.00
sum(Y)	46.00
sum(X^2)	268.00
sum(Y^2)	328.00
Numerator	-298.00
Denominator	323.11
r	-0.9223
r square	0.8506
Xbar(mean)	5.1429
Ybar(mean)	6.5714
SD(X)	3.4480
SD(Y)	1.9720
b	-0.5138
a	9.2138

Correlation coefficient, r = -0.922