Question

Engine Size MPG ar Model A Model B Model C Model D Model E Model F Model G Model H Model I 2.4 2.1 2.6 3.3 3.5 2.2 2.3 2.1 3.8 25 31 25 24 27 25 30 20
b) Calculate the slope and​ y-intercept for the regression equation.

​Therefore, the slope is_____ and the​ y-intercept is_____.

c) Provide an interpretation for the value of the slope.

d) Calculate the SST.

​e) Partition the SST into the SSR and the SSE.

Answer 1

1. Scatter diagram is B)
2. Slope = -4.56395                 Intercept = 37.76712
3. Negative slope indicates that as the size of the sedan car increases it will decrease the MPG.
4. SST = 98.2222
5. SST = SSR + SSE implies 98.2222 = 71.65407 + 26.56815

One can go through the following regression output too.

SUMMARY OUTPUT: Regression of MPG on sedan car size
Regression Statistics
Multiple R	0.854113
R Square	0.72951
Adjusted R Square	0.690868
Standard Error	1.948192
Observations	9
ANOVA
	df	SS	MS	F	Significance F
Regression	1	71.65407	71.65407	18.87894	0.003375
Residual	7	26.56815	3.79545
Total	8	98.22222
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%
Intercept	37.76712	2.909464	12.98078	3.75E-06	30.88733	44.64691
Engine Size	-4.56395	1.050394	-4.34499	0.003375	-7.04774	-2.08017