Question

Vehicle	Weight	MPG
Buick LeSabre	3565	19
Ford Expedition	4855	15
Toyota Corolla	2640	35
Saturn Coupe	2370	28
Ford F-150	3805	15
Pontiac Bonneville	3590	19
Honda Civic	2935	30
Cadilliac Escalade	5115	12
Hummer H1	6600	10
Ford Mustang	3065	20
Lincoln Navigator	3425	16
Dodge Neon	2560	28
Scion xB	2850	36
Chevrolet Camero	3205	19
PT Cruiser	3200	20
Toyota Prius	3950	55

18. Using Excel, conduct a regression analysis for the following data comparing vehicle weight with fuel efficiency, including:

a.    Trendline chart

b.    Equation

c.    Correlation Coefficient

d.    Written characterization of results.

             

19. From the data in problem 18:

a. Is the Toyota Prius mpg an outlier?

b. If not, what MPG would make it an outlier?

Answer 1

18)

a)

b)

using Excel

data > data analysis -> regression

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.4640
R Square	0.2153
Adjusted R Square	0.1593
Standard Error	10.4917
Observations	16
ANOVA
	df	SS	MS	F	Significance F
Regression	1	422.8900	422.8900	3.8418	0.0702
Residual	14	1541.0475	110.0748
Total	15	1963.9375
	Coefficients	Standard Error	t Stat	P-value	Lower 95%
Intercept	40.9603	9.2556	4.4255	0.0006	21.1091
Weight	-0.0048	0.0025	-1.9601	0.0702	-0.0101

y^ = 40.9603 - 0.0048 weight

c)

r= -0.464

d)

p-value of model is 0.07 > alpha

hence the model is not significant at 0.05