A researcher wants to determine the efficacy of a training program directed at improving concentration, focus, and memory on college students.She selects a random sample of 16 individuals and has them take an initial assessment test before the training program.Then the individuals complete the training program, and at the end they take a final test that's comparable to the initial test.The results are shown in the following table: $$\begin{array} { | c | c | c | }
\hline \text { Individ. } & \text { Before } & \text { After } \
\hline 1 & 79 & 81 \
\hline 2 & 74 & 73 \
\hline 3 & 81 & 82.5 \
\hline 4 & 75 & 82.5 \
\hline 5 & 72.5 & 85 \
\hline 6 & 75 & 90 \
\hline 7 & 67.5 & 83.5 \
\hline 8 & 57.5 & 72.5 \
\hline 9 & 62.5 & 87.5 \
\hline 10 & 77.5 & 80 \
\hline 11 & 61.5 & 92.5 \
\hline 12 & 57.5 & 80 \
\hline 13 & 61.5 & 71 \
\hline 14 & 72.5 & 84 \
\hline 15 & 64 & 78.5 \
\hline 16 & 71 & 97.5 \
\hline
\end{array}$$ The analyst uses a Wilcoxon matched-pairs signed rank test with a 0.05 significance level.The appropriate decision is ______.
A)fail to reject the null hypothesis that the before and after scores are different
B)reject the null hypothesis that that the before and after scores are different
C)fail to reject the null hypothesis that the before and after scores are not different
D)reject the null hypothesis that the before and after scores are not different
E)do nothing

Question

A researcher wants to determine the efficacy of a training program directed at improving concentration, focus, and memory on college students.She selects a random sample of 16 individuals and has them take an initial assessment test before the training program.Then the individuals complete the training program, and at the end they take a final test that's comparable to the initial test.The results are shown in the following table: $$\begin{array} { | c | c | c | } 
\hline \text { Individ. } & \text { Before } & \text { After } \
\hline 1 & 79 & 81 \
\hline 2 & 74 & 73 \
\hline 3 & 81 & 82.5 \
\hline 4 & 75 & 82.5 \
\hline 5 & 72.5 & 85 \
\hline 6 & 75 & 90 \
\hline 7 & 67.5 & 83.5 \
\hline 8 & 57.5 & 72.5 \
\hline 9 & 62.5 & 87.5 \
\hline 10 & 77.5 & 80 \
\hline 11 & 61.5 & 92.5 \
\hline 12 & 57.5 & 80 \
\hline 13 & 61.5 & 71 \
\hline 14 & 72.5 & 84 \
\hline 15 & 64 & 78.5 \
\hline 16 & 71 & 97.5 \
\hline
\end{array}$$ The analyst uses a Wilcoxon matched-pairs signed rank test with a 0.05 significance level.The appropriate decision is ______.
A)fail to reject the null hypothesis that the before and after scores are different
B)reject the null hypothesis that that the before and after scores are different
C)fail to reject the null hypothesis that the before and after scores are not different
D)reject the null hypothesis that the before and after scores are not different
E)do nothing

Quizplus · Accepted Answer

The Wilcoxon matched-pairs signed rank test is used to compare two related samples to determine whether their population mean ranks differ. In this context, it's used to assess the impact of the training program on the scores before and after. The null hypothesis typically states that there is no difference between the two sets of scores. Rejecting the null hypothesis (choice D) suggests that there is a statistically significant difference between the before and after scores, implying the training program had an effect.

A Researcher Wants to Determine the Efficacy of a Training