A nonparametric method to compare two populations, when the samples are matched pairs and the data are interval, and where the normality requirement necessary to perform the parametric test is unsatisfied, is the:
A) Wilcoxon rank sum test
B) sign test
C) matched pairs t-test
D) Wilcoxon signed rank test
E) matched pairs z-test

Question

Quizplus · Accepted Answer

The Wilcoxon signed rank test is a nonparametric test that can be used to compare two populations when the samples are matched pairs and the normality assumption is not met. It is suitable for interval data and has the advantage of being more robust than the matched pairs t-test. The sign test is another nonparametric option for comparing paired samples, but it is less powerful than the Wilcoxon signed rank test. The matched pairs t-test and matched pairs z-test are both parametric tests that require normality, so they are not appropriate in this scenario.

A Nonparametric Method to Compare Two Populations, When the Samples