Use the Following Information to Answer the Question $\begin{array}{l}H_{0}: \text { median }=0 \\H_{A}: \text { median } \neq 0\end{array}$

question 15

Multiple Choice

Use the following information to answer the question. Can stretching help you stay alert in class? Thirty-six subjects were
measured for alertness at the beginning of class; the subjects then participated in some light arm and neck stretches followed
by a forty-five minute lecture. Each subject was then measured for alertness at the end of the lecture. The hypothesis test
results for the sign test are summarized below. Assume that all conditions for testing have been met: Hypothesis test results:
Parameter: Median of variable
$\begin{array}{l}H_{0}: \text { median }=0 \\H_{A}: \text { median } \neq 0\end{array}$
$\begin{array}{|l|l|l|l|l|l|l|l|}\hline \text { Variable } & \mathrm{n} & \mathrm{n} \text { for tests } & \text { Sample Median } & \text { Below } & \text { Equal } & \text { Above } & \text { P-value } \\\hline \text { Difference } & 36 & 32 &1& 12 & 4 & 20 & 0.2153 \\\hline\end{array}$
-Choose the correct null and alternative hypothesis.

• A) \( \mathrm{H}_{0} \) : The median difference in alertness is 1 . \( \mathrm{H}_{\mathrm{A}} \) : The median difference in alertness is not 1 .
• B) \( \mathrm{H}_{0} \) : The median difference in alertness is not 0 . \( \mathrm{H}_{\mathrm{A}} \) : The median difference in alertness is 0 .
• C) \( \mathrm{H}_{0} \) : The median difference in alertness is 0 . \( \mathrm{H}_{\mathrm{A}} \) : The median difference in alertness is not 0 .
• D) None of these.

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Definitions:

Position

A specific location or point in space.

Point Bar

A series of low, arcuate ridges of sand and gravel deposited on the inside of a stream bend or meander.

Load Of Sediment

The amount of sediment transported by a fluid, often water or wind, measured over a specific period.

Landslides

Sudden and rapid movement of a large amount of earth material, such as rock and soil, down a slope due to gravity.