In Any Production Process in Which One or More Workers $( y )$

question 75

Multiple Choice

In any production process in which one or more workers are engaged in a variety of tasks, the total time spent in production varies as a function of the size of the workpool and the level of output of the various activities. In a large metropolitan department store, it is believed that the number of man-hours worked $( y )$ per day by the clerical staff depends on the number of pieces of mail processed per day $\left( x _ { 1 } \right)$ and the number of checks cashed per day $\left( x _ { 2 } \right)$ . Data collected for $n = 20$ working days were used to fit the model:
$$E ( y ) = \beta _ { 0 } + \beta _ { 1 } x _ { 1 } + \beta _ { 2 } x _ { 2 }$$
A partial printout for the analysis follows:
$\begin{array} { r r r r r r r r } \hline & & & \text { Actual } & \text { Predict } & & \text { Lower 95\% CL } & \text { Upper 95\% CL } \\\text { OBS } & \text { X1 } & \text { X2 } & \text { Value } & \text { Value } & \text { Residual } & \text { Predict } & \text { Predict } \\& & & & & & & \\1 & 7781 & 644 & 74.707 & 83.175 & - 8.468 & 47.224 & 119.126 \\\hline\end{array}$

Interpret the 95% prediction interval for y shown on the printout.

• A) We are 95% confident that the mean number of man-hours worked per day falls between 47.224 and 119.126 for all days in which 7,781 pieces of mail are processed and 644 checks are
• Cashed.
• B) We are 95% confident that the number of man-hours worked per day falls between 47.224 and 119.126.
• C) We are 95% confident that between 47.224 and 119.126 man-hours will be worked during a single day in which 7,781 pieces of mail are processed and 644 checks are cashed.
• D) We expect to predict number of man-hours worked per day to within an amount between 47.224 and 119.126 of the true value.

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Definitions:

Projection Fibers

Nerve fibers that connect the cerebral cortex to other parts of the brain and to the spinal cord, facilitating communication between the brain and the rest of the body.

Cerebrum

The largest part of the brain, composed of the right and left hemispheres, responsible for complex brain functions such as thought and action.

Spinal Cord

A long, thin, tubular structure made up of nervous tissue, which extends from the brainstem down the back, housed within the spinal column.

Postcentral Gyrus

The region of the cerebral cortex located adjacent to the central sulcus, responsible for processing somatosensory information.