A multiple regression model was developed to predict the fuel efficiency (miles per gallon, mpg) of cars based on three factors: engine size (liters), vehicle weight (kg), and horsepower. We get this multiple regression equation:
MPG = 45.6 − 3.12 × Engine Size − 0.015 × Weight + 0.032 × Horsepower
where:
MPG is the fuel efficiency (miles per gallon).
Engine Size is the engine displacement (liters).
Weight is the vehicle's weight (kg).
Horsepower is the engine's power output.
Identify the response and predictor variables.