ASB Session 3

Which of the following statements correctly differentiates the assumptions between the Wilcoxon Signed Rank Test and the Paired t-test?

• Both tests assume normally distributed paired differences and require interval-scale data.

• The Paired t-test assumes normality of paired differences, while the Wilcoxon Signed Rank test assumes the differences are symmetrically distributed.

• The Wilcoxon Signed Rank test assumes normality, whereas the Paired t-test only assumes independent observations.

• Both tests assume the samples are independent and drawn from identical distributions.

You are comparing the effectiveness of two diets on weight loss in the same group of 25 individuals, measured before and after the intervention. The data are not normally distributed. Which test is most appropriate?

• Independent two-sample t-test

• Wilcoxon rank sum test

• Paired t-test

• Wilcoxon signed rank test

Which of the following correctly matches tests to the nature of their sample structures?

• Wilcoxon Signed Rank Test and Paired t-test → Independent samples

• Wilcoxon Rank Sum Test and Independent t-test → Dependent (paired) samples

• Wilcoxon Rank Sum Test and Independent t-test → Independent samples

• All four tests require independent samples

If the assumption of normality is violated, but samples are still independent, which test is more appropriate to compare two groups?

• Wilcoxon Rank Sum Test

• Independent t-test

• Paired t-test

• Wilcoxon Signed Rank Test

Which of the following statements is false?

• The Wilcoxon Signed Rank test does not require the data to be normally distributed.

• The Independent t-test assumes equal variances between groups.

• The Wilcoxon Rank Sum Test can be used as a non-parametric alternative to the Paired t-test.

• The Paired t-test is sensitive to outliers in the difference scores.

Which of the following best explains why a researcher might prefer the Wilcoxon Rank Sum Test over the Independent samples t-test?

• The data are normally distributed and measured on an interval scale.

• The sample size is small, and the distribution of the data is heavily skewed with outliers.

• The samples are paired and measured at two different time points.

• The sample size is large and the population variances are unequal.

A researcher collects blood pressure measurements before and after administering a new medication to 30 patients. The differences in blood pressure scores are normally distributed. Which test should the researcher use to determine if the medication had a significant effect?

• Wilcoxon Signed Rank Test

• Independent Samples t-test

• Wilcoxon Rank Sum Test

• Paired t-test