Question

x	42	38	44	25	21	42	35	51	33
y	21	25	22	28	30	27	21	13	21

1.)Do heavier cars really use more gasoline? Suppose a car is chosen at random. Let x be the weight of the car (in hundreds of pounds), and let y be the miles per gallon (mpg). Write out the least-squares line y=a+bx

2.)Do heavier cars really use more gasoline? Suppose a car is chosen at random. Let x be the weight of the car (in hundreds of pounds), and let y be the miles per gallon (mpg). The estimate y value found in the previous question is _____ (answers are either: an extrapolation, an interpolation, an error, or a residual)

Answer 1

1. y = 38.2620 - 0.4120*x

2. an interpolation

	r²	0.587
	r	-0.766
	Std. Error	3.494
	n	9
	k	1
	Dep. Var.	y
ANOVA table
Source	SS	df	MS	F	p-value
Regression	121.4356	1	121.4356	9.95	.0161
Residual	85.4533	7	12.2076
Total	206.8889	8
Regression output				confidence interval
variables	coefficients	std. error	t (df=7)	p-value	95% lower	95% upper
Intercept	38.2620
x	-0.4120	0.1306	-3.154	.0161	-0.7208	-0.1031