The Buyer's Guide section of the Web site for Car and Driver magazine provides reviews and road tests for cars, trucks, SUVs and vans. The average ratings of overall quality, handling, dependability, and fit & finish for each vehicle using a scale ranging from 1 (worst) to 10 (best) can be found on our Final Exam Answer Sheet. Assuming α=.05 for this problem with all regression assumptions holding.
a. Develop an estimated regression equation using handling, dependability, and fit & finish to predict overall quality
b. Is the estimated regression equation significant? Why?
c. How much of the total variation is being explained by the regression equation?
d. Are any of the independent variables not significant? Which one(s)?
e. Another Sports/GT car rated by Car and Driver is the Honda Accord. The ratings for handling, dependability, and fit & finish for this car were 8.28, 9.06, 8.07, respectively. Estimate the overall rating for this car.
f. The overall rating reported by Car and Driver for the Honda Accord was 8.65. Why is this number different from what your found in part (e).
g. In this estimated regression equation, are there any outliers? If so, which variables are outliers?
Sports/GT Overall Handling Dependability Fit and Finish
Acura 3.2CL 7.8 7.83 8.17 7.67
Acura RSX 9.02 9.46 9.35 8.97
Audi TT 9 9.58 8.74 9.38
BMW 3-Series/M3 8.39 9.52 8.39 8.55
Chevrolet Corvette 8.82 9.64 8.54 7.87
Ford Mustang 8.34 8.85 8.7 7.34
Honda Civic Si 8.92 9.31 9.5 7.93
Infiniti G35 8.7 9.34 8.96 8.07
Mazda RX-8 8.58 9.79 8.96 8.12
Mini Cooper 8.76 10 8.69 8.33
Mitsubishi Eclipse 8.17 8.95 8.25 7.36
Nissan 350Z 8.07 9.35 7.56 8.21
Porsche 911 9.55 9.91 8.86 9.55
Toyota Celica 8.77 9.29 9.04 7.97