SCENARIO 14-15
the Superintendent of a School District Wanted to Predict

question 357

True/False

SCENARIO 14-15
The superintendent of a school district wanted to predict the percentage of students passing a sixth-
grade proficiency test. She obtained the data on percentage of students passing the proficiency test
(% Passing), mean teacher salary in thousands of dollars (Salaries), and instructional spending per
pupil in thousands of dollars (Spending) of 47 schools in the state. Following is the multiple regression output with $Y = \%$ Passing as the dependent variable, $X _ { 1 } =$
Salaries and $X _ { 2 } =$ Spending:

$\begin{array}{lr}\hline {\text { Regression Statistics }} \\\hline \text { Multiple R } & 0.4276 \\\text { R Square } & 0.1828 \\\text { Adjusted R Square } & 0.1457 \\\text { Standard Error } & 5.7351 \\\text { Observations } & 47 \\\hline\end{array}$

ANOVA


$\begin{array}{lrrrrrr}\hline & \text { Coefficients } & \text { Standard Error } & \text { t Stat } & \rho \text {-value } & \text { Lower 95\% } & \text { Upper 95\% } \\\hline \text { Intercept } & -72.9916 & 45.9106 & -1.5899 & 0.1190 & -165.5184 & 19.5352 \\\text { Salary } & 2.7939 & 0.8974 & 3.1133 & 0.0032 & 0.9853 & 4.6025 \\\text { Spending } & 0.3742 & 0.9782 & 0.3825 & 0.7039 & -1.5972 & 2.3455 \\\hline\end{array}$

-Referring to Scenario 14-15, you can conclude definitively that instructional
spending per pupil individually has no impact on the mean percentage of students passing the
proficiency test, taking into account the effect of mean teacher salary, at a 10% level of
significance based solely on but not actually computing the 90% confidence interval estimate for $\beta _ { 2 }$ .

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Definitions:

Marginal Cost

The additional cost associated with producing one more unit of output.

Profit Maximizing

The process or strategy of adjusting production levels, pricing, and other operational parameters to achieve the highest possible profit.

Kinked Demand Curve

A concept in economics describing a situation where a firm's demand curve has a distinct kink due to competitors only matching price increases but not price decreases, leading to price rigidity.

Marginal Cost

The extra expense associated with the production of an additional unit of a product or service.