TABLE 13-9
It Is Believed That, the Average Numbers of Hours

question 65

Multiple Choice

TABLE 13-9
It is believed that, the average numbers of hours spent studying per day (HOURS) during undergraduate education should have a positive linear relationship with the starting salary (SALARY, measured in thousands of dollars per month) after graduation. Given below is the Excel output from regressing starting salary on number of hours spent studying per day for a sample of 51 students. NOTE: Some of the numbers in the output are purposely erased.
$$\begin{array}{l}\text { Regression Statistics }\\\begin{array} { l c } \hline \text { Multiple R } & 0.8857 \\\text { R Square } & 0.7845 \\\text { Adjusted R Square } & 0.7801 \\\text { Standard Error } & 1.3704 \\\text { Observations } & 51 \\\hline\end{array}\end{array}$$
$\text { ANOVA }$
$\begin{array}{llcc}\hline&\text { df }&\text { SS } &\text { MS }&\text {F }&\text { Significance F } \\\text { Regression } & 1 & 335.0472 & 335.0473 & 178.3859 \\\text { Residual } & & & 1.8782 & \\\text { Total } & 50 & 427.0798 & &\end{array}$
-Referring to Table 13-9, the 90% confidence interval for the average change in SALARY (in thousands of dollars) as a result of spending an extra hour per day studying is

• A) wider than [-2.70159, -1.08654].
• B) wider than [0.8321927, 1.12697].
• C) narrower than [0.8321927, 1.12697].
• D) narrower than [-2.70159, -1.08654].

---

Definitions:

Necrosis

The death of cells or tissue in the body due to disease, injury, or lack of blood supply.

Intramuscular Injection

A method of delivering medication deep into the muscles, allowing for faster absorption than subcutaneous injections.

Reflection

The process of serious thought or consideration.

Fist Fight

A form of physical altercation involving the use of fists to punch the opponent, typically occurring in impromptu or informal settings.