Question

Price	Miles	Weight	Age
13500	4995	1165	2
13750	5048	1160	2
13950	4874	1165	1
13950	4536	1165	1
13750	5300	1170	2
14800	4125	1165	1
13750	4895	1170	1
13950	4325	1165	2
13700	5000	1165	2
12500	8500	1170	3
11500	9578	1160	3
12400	5675	1165	2
11850	9857	1170	4
10900	10240	1165	4
11450	10253	1170	3

.Please use Excel if you can

A. Estimate a regression model for "Price" = "Miles".

B. Estimate a regression model for "Price" = "Age".

C. If sales is the dependent variable, which of the two independent variables do you think explains sales better? Explain

D. Estimate a Regreesion model for "Price" ="Miles" + "Age" +"Weight", and explain the model fit and the significant variables.

Answer 1

A)

Regression Statistics
Multiple R	0.944648
R Square	0.89236
Adjusted R Square	0.88408
Standard Error	400.1421
Observations	15
ANOVA
	df	SS	MS	F	Significance F
Regression	1	17255855	17255855	107.7725	1.16E-07
Residual	13	2081478	160113.7
Total	14	19337333
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 95.0%	Upper 95.0%
Intercept	16037.54	306.0658	52.399	1.64E-16	15376.33	16698.76	15376.33	16698.76
Miles	-0.46155	0.04446	-10.3814	1.16E-07	-0.5576	-0.3655	-0.5576	-0.3655

B)

Regression Statistics
Multiple R	0.877327
R Square	0.769703
Adjusted R Square	0.751988
Standard Error	585.2898
Observations	15

	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 95.0%	Upper 95.0%
Intercept	15283.33	371.4528	41.14475	3.72E-15	14480.86	16085.81	14480.86	16085.81
Age	-1016.67	154.2374	-6.59157	1.74E-05	-1349.88	-683.457	-1349.88	-683.457

C)

Sales will depend on price and miles.

d)

Regression Statistics
Multiple R	0.95175
R Square	0.905828
Adjusted R Square	0.880145
Standard Error	406.8757
Observations	15

	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 95.0%	Upper 95.0%
Intercept	-23452.8	38452.79	-0.60991	0.554311	-108087	61181.26	-108087	61181.26
Miles	-0.41405	0.104187	-3.9741	0.002181	-0.64337	-0.18474	-0.64337	-0.18474
Weight	33.89045	33.03599	1.025865	0.326986	-38.8213	106.6022	-38.8213	106.6022
Age	-151.708	244.3067	-0.62097	0.547269	-689.423	386.0077	-689.423	386.0077

Please revert back in case of any doubt.

Please upvote. Thanks in advance.