TABLE 15-5 What Are the Factors That Determine the Acceleration Time (In

Multiple Choice

TABLE 15-5
What are the factors that determine the acceleration time (in sec.) from 0 to 60 miles per hour of a car? Data on the following variables for 171 different vehicle models were collected:
Accel Time: Acceleration time in sec.
Cargo Vol: Cargo volume in cu. ft.
HP: Horsepower
MPG: Miles per gallon
SUV: 1 if the vehicle model is an SUV with Coupe as the base when SUV and Sedan are both 0
Sedan: 1 if the vehicle model is a sedan with Coupe as the base when SUV and Sedan are both 0
The regression results using acceleration time as the dependent variable and the remaining variables as the independent variables are presented below.
ANOVA
The various residual plots are as shown below.
The coefficient of partial determination ( ) of each of the 5 predictors are, respectively, 0.0380, 0.4376, 0.0248, 0.0188, and 0.0312.
The coefficient of multiple determination for the regression model using each of the 5 variables as the dependent variable and all other X variables as independent variables ( ) are, respectively, 0.7461, 0.5676, 0.6764, 0.8582, 0.6632.
-Referring to Table 15-5, what is the correct interpretation for the estimated coefficient for HP?

A) As the horsepower increases by one unit, the mean 0 to 60 miles per hour acceleration time will decrease by an estimated 0.0200 seconds without taking into consideration all the other independent variables included in the model.
B) As the 0 to 60 miles per hour acceleration time increases by one second, the mean horsepower will decrease by an estimated 0.0200 unit without taking into consideration all the other independent variables included in the model.
C) As the horsepower increases by one unit, the mean 0 to 60 miles per hour acceleration time will decrease by an estimated 0.0200 seconds taking into consideration all the other independent variables included in the model.
D) As the 0 to 60 miles per hour acceleration time increases by one second, the mean horsepower will decrease by an estimated 0.0200 unit taking into consideration all the other independent variables included in the model.