Annual income is known to form a skewed distribution but a researcher wants to know if there is a difference in the distributions of income for men and women in her company. She obtains a random sample of each, converts their annual income into ranks, and then uses the _____________________ test to determine if the overall salaries of one gender differ significantly from the other.
A) Mann-Whitney test
B) Wilcoxon matched-pairs signed-ranks test
C) Kruskal-Wallis test
D) Spearman test

Question

Quizplus · Accepted Answer

The Mann-Whitney test is the appropriate non-parametric test to compare the distributions of two independent groups when the data is not normally distributed, such as in the case of skewed income distributions. The Wilcoxon matched-pairs signed-ranks test is used to compare two related samples, the Kruskal-Wallis test is used to compare three or more independent groups, and the Spearman test is used to assess the correlation between two variables.

Annual Income Is Known to Form a Skewed Distribution but a Researcher