22; 23; 24 2024 \begin{tabular}{|l|l|l|l|l|l|} \hline & Q.1.1.2 & \multicolumn{3}{|c|}{Explain why the normality of the data should be assessed and use measures of central tendency to comment on the normality of the data in each sample.} & (5) \\ \hline & Q.1.1.3 & & Calculate the standard deviations of each sample (the experimental group and the control group), showing your working. & & (5) \\ \hline & \multicolumn{4}{|l|}{Hypothesis testing} & \\ \hline & Q.1.1.4 & & State the hypotheses both numerically and written & & (4) \\ \hline & Q.1.1.5 & & State the decision criteria. & & (4) \\ \hline & Q.1.1.6 & & Calculate the test statistic. & & (5) \\ \hline & Q.1.1.7 & \multicolumn{3}{|c|}{Make a decision about whether to reject the null hypothesis.} & (2) \\ \hline \multirow[t]{12}{*}{Q.1.2} & \multicolumn{4}{|l|}{Does caffeine affect academic performance?} & \multirow{12}{*}{} \\ \hline & & & A researcher believes that caffeine affects academic performance. She wants to test to see whether this is true or not. She decides that she will compare the test scores of a group of students before and after they are given caffeine to investigate this hypothesis. & & \\ \hline & \multicolumn{4}{|c|}{TEST SCORES} & \\ \hline & \multicolumn{2}{|c|}{Participants} & Before Caffeine & After Caffeine & \\ \hline & \multicolumn{2}{|c|}{1} & 3 & 10 & \\ \hline & \multicolumn{2}{|c|}{2} & 3 & 8 & \\ \hline & \multicolumn{2}{|c|}{3} & 4 & 9 & \\ \hline & \multicolumn{2}{|c|}{4} & 7 & 8 & \\ \hline & \multicolumn{2}{|c|}{5} & 2 & 6 & \\ \hline & \multicolumn{2}{|c|}{6} & 5 & 7 & \\ \hline & \multicolumn{2}{|c|}{7} & 8 & 6 & \\ \hline & \multicolumn{2}{|c|}{8} & 8 & 7 & \\ \hline & \multicolumn{4}{|c|}{Q.1.2.1 State the hypotheses both numerically and written} & (4) \\ \hline & Q.1.2.2 & \multicolumn{3}{|c|}{State the decision criteria.} & (4) \\ \hline & Q.1.2.3 & \multicolumn{3}{|c|}{Calculate the test statistic.} & (5) \\ \hline & Q.1.2.4 & \multicolumn{3}{|c|}{Make a decision about whether to reject the null hypothesis.} & (2) \\ \hline \end{tabular}
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- Normality should be assessed to determine if parametric tests can be used, which assume normal distribution. - Calculate the mean, median, and mode for each sample to assess symmetry. - If mean ≈ median ≈ mode, the data is likely normal. Show more…
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