This article describes how to perform the Wilcoxon ranksum test to compare the median between two samples.
This test can be applied to two samples of equal or different sizes. For paired samples see Test  Nonparametric  Paired Samples Wilcoxon Test.
Requirements
A Displayr document with a data set.
Method
 Go to Anything > Advanced Analysis > Test > Nonparametric > Two Sample Wilcoxon Rank Sum Test.
 Specify the outcome variable to use under Inputs > TwoSample Wilcoxon Test > Outcome. The outcome variable is the variable containing the sample to analyze.
 Under Inputs > TwoSample Wilcoxon Test > Group, specify the variable that each observation comes from. Where this variable is numeric, it is automatically grouped into two approximately equally sized groups, using the median, and will be automatically converted by the function.
OPTIONAL: You can modify the following settings to adjust the output:
 mu  Difference in the median of the two samples, as assumed under the null hypothesis.
 Alternative hypothesis  Use a twosided or onesided test.
 Type of test  Method by which the pvalue is computed.

Output
 Summary  Shows a nicely formatted table of the test results (default).
 R  The original textbased output from the wilcox.test function.
 Variable names  Display Variable Names in the output, instead of Variable Labels.
 More decimal places  Display numeric values with 8 decimal places.
Next
How to Perform Paired Samples Wilcoxon Test