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:

Consumer Price Index

A measure that examines the weighted average of prices of a basket of consumer goods and services, such as transportation, food, and medical care, used to estimate cost of living changes.

Market Basket

A selected group of goods and services used to track inflation and other economic indicators through price changes.

Base Year

A specific year against which economic growth is measured, serving as a standard point of comparison for real economic calculations such as GDP.

Consumer Price Index

An index that measures the average change over time in the prices paid by urban consumers for a market basket of consumer goods and services.