An Instructor Gives a Test Before and After a Lesson

question 40

Essay

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

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Definitions:

Vervet Monkey

A medium-sized primate species known for its black face and grey body fur, native to Africa.

Bottlenose Dolphin

A widely distributed and commonly known species of dolphin characterized by its large size, intelligence, and complex behaviors.

Courtship Communication

The exchange of signals between members of a species to attract mates and facilitate reproductive behaviors.

Mothering Style

The distinctive approach or method that a mother uses in raising her offspring, influencing their psychological and emotional development.