In a manufacturing facility producing fasteners,a foreman suspects that the diameter of the bolt produced by his second shift workers is greater than the diameter of the bolts produced by his first shift workers.He takes a sample of 5 bolts from the first shift and a sample of 4 bolts from the second shift and measures the diameters in inches.Distribution of bolt diameter measurements is not normally distributed.Which one of the following nonparametric tests is appropriate for this problem?
A)Wilcoxon signed rank test
B)Wilcoxon rank sum test
C)Sign test
D)Kruskal-Wallis test
E)Spearman's rank correlation test

Question

Quizplus · Accepted Answer

The Wilcoxon rank sum test (also known as Mann-Whitney U test) is appropriate when comparing two independent samples that do not follow a normal distribution. In this case, the samples are from different shifts, and the distribution of bolt diameter measurements is not normally distributed. The Wilcoxon signed rank test is for dependent samples, the sign test is only suitable for a one-sample problem, the Kruskal-Wallis test is for comparing more than two groups, and Spearman's rank correlation test is for assessing the correlation between two variables.

In a Manufacturing Facility Producing Fasteners,a Foreman Suspects That the Diameter