Instruction 13-8
You Worked as an Intern at We Always

Instruction 13-8
You worked as an intern at We Always Win Car Insurance Company last summer.You notice that individual car insurance premium depends very much on the age of the individual,the number of traffic tickets received by the individual,and the population density of the city in which the individual lives.You performed a regression analysis in Microsoft Excel and obtained the following information:
$\begin{array}{l}\text { Regression Analysis }\\\begin{array}{lr}\hline {\text { Regression Statistics }} \\\hline \text { Multiple R } & 0.63 \\\text { R Square } & 0.40 \\\text { Adjusted R Square } & 0.23 \\\text { Standard Error } & 50.00 \\\text { Observations } & 15.00\end{array}\end{array}$
ANOVA
$\begin{array}{lrrrrrr} & d f & & S S & M S & F & \text { Significance } F \\\hline \text { Regression } & 3 & & 5994.24 & 2.40 & 0.12 \\\text { Residual } & 11 & 27496.82 & & & \\\text { Total } & & 45479.54 & & &\end{array}$

$\begin{array}{lrrrrrrr} & \text { Coefficients } & \text { Standard } & t \text { Stat } & \text { P-value } & \text { Lower 99.0\% } & \text { Upper 99.0\% } \\\hline \text { Intercept } & {\text { Error }} & & & & & \\\text { AGE } & 123.80 & 48.71 & 2.54 & 0.03 & -27.47 & 275.07 \\\text { TICKETS } & -0.82 & 0.87 & -0.95 & 0.36 & -3.51 & 1.87 \\\text { DENSITY } & 21.25 & 10.66 & 1.99 & 0.07 & -11.86 & 54.37 \\& -3.14 & 6.46 & -0.49 & 0.64 & -23.19 & 16.91\end{array}$
-Referring to Instruction 13-8,the 99% confidence interval for the change in average insurance premiums of a person who has become one year older (i.e. ,the slope coefficient for AGE)is ________.