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:

Marginal Cost

Expenses incurred in creating one more unit of a product.

Perfect Competition

A market structure characterized by a large number of buyers and sellers, identical products, and no barriers to entry or exit.

Perfect Competition

A market structure characterized by an infinite number of small firms, identical products, no barriers to entry or exit, and perfect information, leading to price takers.

Patents and Copyrights

Legal protections for inventors and creators to exclusively commercialize their innovations and creative works for a certain period.