Question

Here is a bivariate data set.

x	y
38	12
36	19
26	-17
36	35
40	35
44	48
43	23
25	26
47	62
48	53

Find the correlation coefficient and report it accurate to four decimal places.
r =

Answer 1

Solution:

X	Y	XY	X^2	Y^2
38	12	456	1444	144
36	19	684	1296	361
26	17	442	676	289
36	35	1260	1296	1225
40	35	1400	1600	1225
44	48	2112	1936	2304
43	23	989	1849	529
25	26	650	625	676
47	62	2914	2209	3844
48	53	2544	2304	2809

n	10
sum(XY)	13451.00
sum(X)	383.00
sum(Y)	330.00
sum(X^2)	15235.00
sum(Y^2)	13406.00
Numerator	8120.00
Denominator	11934.44
r	0.6804
r square	0.4629
Xbar(mean)	38.3000
Ybar(mean)	33.0000
SD(X)	5.4975
SD(Y)	12.6183
b	1.4344
a	-21.9366

r = 0.6804