Independent random samples from two populations are shown below.
Sample A: 11, 15, 18, 21
Sample B: 9, 12, 15, 17, 20, 23
Calculate the rank sum for each sample. Which would be used as the test statistic in a Wilcoxon rank sum test?

Question

Quizplus · Accepted Answer

The Answer is Population A:

T _ { 1 } = 2 + 4.5 + 7 + 9 = 22.5

Population B:

T _ { 2 } = 1 + 3 + 4.5 + 6 + 8 + 10 = 32.5

The test statistic is

T _ { 1 } = 22.5

since it corresponds to the smaller sample.

Independent Random Samples from Two Populations Are Shown Below