416 Appendix A: Description of Data Sets Engine_Cylinders Mpg_City Mpg_Hwy Mpg_Hwy_Minus_City Hybrid Notes the number of cylinders in the engine the EPA miles-per-gallon (MPG) estimate for city driving the EPA MPG estimate for highway driving the difference betwee the MPG estimates for city and highway driving an indicator variable that contains the value 1 if the vehicle is a hybrid- electric vehicle a variable that indicates whether the vehicle is one of the following kinds of vehicles: E85 Gas HEV Tax the MPG estimates for this vehicle were measured for E85 fuel the MPG estimates for this vehicle were measured for gasoline the vehicle is a hybrid-electric vehicle the vehicle is subject to a "gas guzzler" tax as required by the Energy Tax Act of 1978. The tax does not apply to light trucks. A.3 Movies Data