2004 Car Prices
Scott Ning
Sean Meade
Predict vehicle retail price
Sports Car
Sport Utility Vehicle
Wagon
Minivan
Pickup
All-Wheel Drive
Rear-Wheel Drive
Suggested Retail Price, what the manufacturer thinks the vehicle is worth, including
adequate profit for the automaker and the dealer ($ Dollars)
Dealer Cost (or "invoice price"), what the dealership pays the manufacturer ($)
Engine Size (liters)
Number of Cylinders
Horsepower
City Miles Per Gallon
Highway Miles Per Gallon
Weight (Pounds)
Wheel Base (inches)
Length (inches)
Width (inches)
Correlation
SportsCar SportsUtility Wagon Minivan Pickup All-WheelDrive
Price 0.38186 0.04193 -0.05565 -0.05679 -0.09837 0.09999
Rear-WheelDrive DealerCost EngineSize Cylinders HP
Price 0.40359 0.99913 0.57175 0.62876 0.82695
city_mpg mpg pounds wheel length width
Price -0.46113 -0.42940 0.44934 0.15035 0.21489 0.32811
Original Equation
Price = -2441.74290 + (394.86928*sc) + (300.23290*su) - (98.50362*wagon) +
(315.97925*minivan) + (0*pickup) + (250.71560*awd) + (150.49711*rwd) +
(1.08958*dealerCost) + (193.70722*size) – (31.82502*cylinders) + (1.03945*hp) –
(12.17910*cityMPG) + (35.98411*highwayMPG) – (0.03931*pounds) - (46.61526*wheel) +
(15.35560*length) + (41.49026*width)
Backward Elimination
Price = -2341.72702 + (322.32671*sc) + (1.09095*dealerCost) +
(182.18777*size) – (30.47070*wheel) + (70.47453*width)
R-Squared Selection
Goodness of Fit
F-Test
F-value is very high
P-value is less than 0.0001
Therefore, test value is significant
Model has predictive value
Normality
Data is heavily left-skewed
Assumption of normality not met
VIF
Which car type?
Sports Sports Wagon Mini Pickup
car Util Van
Which car type?
Sports Sports Wagon Mini Pickup
car Util Van