An Instructor Gives a Test Before and After a Lesson

question 28

Essay

An instructor gives a test before and after a lesson and results from randomly selected students are given below.
Use Wilcoxon's signed-ranks test and a 0.05 significance level to test the claim that the lesson has no effect on
the grade. $$\begin{array} { l l l l l l l l l l l l l l l l } \text { Before } & 54 & 61 & 56 & 41 & 38 & 57 & 42 & 71 & 88 & 42 & 36 & 23 & 22 & 46 & 51 \\\hline \text { After } & 82 & 87 & 84 & 76 & 79 & 87 & 42 & 97 & 99 & 74 & 85 & 96 & 67 & 84 & 79\end{array}$$

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Definitions:

Bretton Woods Accord

An agreement established in 1944 that set the exchange rate system and established the International Monetary Fund and the World Bank.

Fixed

Expenses that remain constant for a period of time and do not vary with production levels or sales volume.

Specified Levels

Predetermined benchmarks or criteria that need to be met within certain contexts, such as quality standards or performance thresholds.

Hedging

A risk management strategy used to reduce or limit potential losses by taking offsetting positions in related securities or derivatives.