A Researcher Wants to Determine the Efficacy of a Training

question 64

Multiple Choice

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 observed z score is ______.

• A)-3.4645
• B)-3.2157
• C)-3.0178
• D)-2.9857
• E)-2.7978

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Definitions:

Delinquent Activity

Behavior, especially of a young person, that deviates from legal or social norms and may result in criminal actions.

Identity Development

The process by which a person develops a distinct sense of self throughout their life, often influenced by various social, cultural, and personal factors.

Conflict With Peers

Situations where disagreements or disputes arise between individuals of similar age groups, often leading to social stress or development of conflict resolution skills.

Maladjustment

Failure to adjust appropriately to environmental circumstances or to the demands of society or personal expectations.