A nonparametric method that is equivalent to the Wilcoxon rank sum test is the:
A) Wilcoxon signed rank sum test
B) Friedman test
C) Kruskal-Wallis test
D) Mann-Whitney test
E) chi-square test

Question

Quizplus · Accepted Answer

The Mann-Whitney test is the nonparametric equivalent to the Wilcoxon rank sum test, which is used to compare two independent groups. The other answer choices are nonparametric tests, but they are not equivalent to the Wilcoxon rank sum test. The Wilcoxon signed rank sum test is used to compare paired samples, the Friedman test is used to compare three or more related groups, the Kruskal-Wallis test is used to compare three or more independent groups, and the chi-square test is used to compare categorical variables.

A Nonparametric Method That Is Equivalent to the Wilcoxon Rank