Instruction 13-12
An automotive engineer would like to be able to predict automobile fuel economy.She believes that the two most important characteristics that affect economy are engine power and the number of cylinders (4 or 6) of a car.She believes that the appropriate model is
Y = 40 - 0.05X₁ + 20X₂ - 0.1X₁X₂
where X₁ = engine power
X₂ = 1 if 4 cylinders,0 if 6 cylinders
Y = economy expressed as kilometres.
-Referring to Instruction 13-12,the fitted model for predicting economy for 6-cylinder cars is ________.

Question

Quizplus · Accepted Answer

The fitted model for predicting economy for 6-cylinder cars is 40 - 0.05X₁. This is because the term 20XS1U1B12S1U1B0 - 0.1XS1U1B11S1U1B0XS1U1B12S1U1B0 is equal to 0 when XS1U1B12S1U1B0 = 0 (i.e., for 6-cylinder cars).

Instruction 13-12 An Automotive Engineer Would Like to Be Able to Predict