Using the Wilcoxon Rank Sum Test analyze the following data

Using the Wilcoxon Rank Sum Test, analyze the following data for evidence that population B is different from population A.

16.Give the sum of ranks for sample B.

17. Give the value of the Z-statistic based on the sum of ranks in # 16

18. Which of the following correctly describes the p-value for the test statistic in #17?

19. What is the decision at the .05 significance level?

We have performed the test using MS_EXCEL addin Real Statistics . The results are as follows.

16.

Sum of ranks for sample B = 181

17.

Z-statistic = 1.789786

18.

P-value = 0.073488

19.

Since the P-value is greater than 0.05 , the distribution in two groups is not different.

Mann-Whitney Test for Two Independent Samples

	A	B
count	12	12
median	227	243
rank sum	119	181
U	103	41

	one tail	two tail
alpha	0.05
U	41
mean	72
std dev	17.32051
z-score	1.789786
effect r	0.365339
U-crit	43.5103	38.05243
p-value	0.036744	0.073488
sig (norm)	yes	no