Gas mileage revisited. Let s try the re-expressed variable Fuel Consumption (gal/100 mi) to examine the fuel efficiency of the 11 cars in given Exercise. Here are the revised regression analysis and residuals plot:
a) Explain why this model appears to be better than the linear model.
b) Using the regression analysis above, write an equation of this model.
c) Interpret the slope of this line.
d) Based on this model, how many miles per gallon would you expect a 3500-pound car to get?
Exercise :
Gas mileage. As the example in the chapter indicates, one of the important factors determining a car s Fuel Efficiency is its Weight. Let's examine this relationship again, for 11 cars.
a) Describe the association between these variables shown in the scatterplot.
b) Here is the regression analysis for the linear model. What does the slope of the line say about this relationship?
c) Do you think this linear model is appropriate? Use the residuals plot to explain your decision.
