Question

The table shows the number of people living in a house and the weight of trash (in pounds) at the curb just before the trash pickup. People(x) Trash(y) Zx -0.4392 0.1464 1.3175 - 1.0247 Zy -0.6838 -0.2519 1.4756 -0.5399 93 23 Compute the correlation coefficient (r) between the number of people and the weight of trash. a. None of the choices b. 0.6902 c. 0.3944 d. 0.9202 e. 0.0000

The table shows the number of people living in a house and the weight of trash (in pounds) at the curb just before the trash pickup.

People(x) Trash(y) Zx Zy

2 18 -0.4392 -0.6838

3 33 0.1464 -0.2519

5 93 1.3175 1.4756

1 23 -1.0247 -0.5399

Answer 1

	X	Y	X^2	Y^2	XY
	2	18	4	324	36
	3	33	9	1089	99
	5	93	25	8649	465
	1	23	1	529	23
Total	11	167	39	10591	623

$SS_x = \sum X^2 - \frac{(\sum X)^2}{n} = 39-\frac{11^2}{4} = 8.75$

$SS_y = \sum Y^2 - \frac{(\sum Y)^2}{n} = 10591-\frac{167^2}{4} = 3618.75$

$SS_xy = \sum XY - \frac{\sum X \sum Y}{n} = 623-\frac{167*11}{4} = 163.75$

$r = \frac{SS_xy }{\sqrt{SS_ySS_x}}$

$r = \frac{163.75 }{\sqrt{3618.75*8.75}}$

r = 0.9202