SCENARIO 14-16
What Are the Factors That Determine the Acceleration $Y$

SCENARIO 14-16
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 30 different vehicle models were collected: $Y$ (Accel Time) : Acceleration time in sec.
$X _ { I }$ (Engine Size) : c.c.
$X _ { 2 }$ (Sedan) : 1 if the vehicle model is a sedan and 0 otherwise

The regression results using acceleration time as the dependent variable and the remaining variables as the independent variables are presented below.

$\begin{array}{lr}\hline{\text { Regression Statistics }} \\\hline \text { Multiple R } & 0.6096 \\\text { R Square } & 0.3716 \\\text { Adjusted R Square } & 0.3251 \\\text { Standard Error } & 1.4629 \\\text { Observations } & 30 \\\hline\end{array}$

ANOVA



$\begin{array}{lrrrrrr}\hline & \text { Coefficients } & \text { Standard Error } & \text { t Stat } & \text { P-value } & \text { Lower 95\% } & \text { Upper 95\% } \\\hline \text { Intercept } & 7.1052 & 0.6574 & 10.8086 & 0.0000 & 5.7564 & 8.4540 \\\text { Engine Size } & -0.0005 & 0.0001 & -3.6477 & 0.0011 & -0.0008 & -0.0002 \\\text { Sedan } & 0.7264 & 0.5564 & 1.3056 & 0.2027 & -0.4152 & 1.8681 \\\hline\end{array}$


-Referring to Scenario 14-16, what is the correct interpretation for the estimated coefficient for $X _ { 2 }$ ?

A) The mean 0 to 60 miles per hour acceleration time of a sedan is estimated to be 0.7264 seconds lower than that of a non-sedan after considering the effect of the engine size.
B) The mean 0 to 60 miles per hour acceleration time of a sedan is estimated to be 0.7264 seconds higher than that of a non-sedan after considering the effect of the engine size.
C) The mean 0 to 60 miles per hour acceleration time of a sedan is estimated to be 0.7264 seconds lower than that of a non-sedan without considering the effect of the engine size.
D) The mean 0 to 60 miles per hour acceleration time of a sedan is estimated to be 0.7264 seconds higher than that of a non-sedan without considering the effect of the engine size.