What attributes make a car accelerate better? Surely you will think that, like most, the power, aerodynamic design and the type of transmission. To verify this, use the data from Cars to model the time it takes for a vehicle to go from 0-60 miles per hour. Variables are defined below S: The time (in seconds) it takes the car to accelerate to 60 mph T: Dummy Variable (1.- If it has a manual transmission, 0.- any other type) P: Weight in pounds without passengers E: Coefficient of resistance H: horse power

a) Estimate the regression equation that models S=f(T,P,E,H) b) Suppose your neighbor has a PhD in Physics and tells you that the power (H) of a car can be expressed in terms of the following equation: H=(M*D*A)/s, where M: Mass, D: Distance and A: Acceleration; S as defined above. Based on the information above, you decide to change the functional form of the relationship between S and H to an inverse relationship. Estimate a new equation that models S=f(T,P,E,1/H) c) Which of the two equations seems to be the best? Use Schwarz Criterion to justify your answer.

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