Wilcoxon Mann Whitney U Test. Freidlin gastwirth 2000 advocate the retirement of the median test from general use being replaced by the wilcoxon mann whitney and related tests. The mann whitney u test sometimes called the mann whitney wilcoxon test or the wilcoxon rank sum test is used to test whether two samples are likely to derive from the same population i e that the two populations have the same shape.
A mann whitney u test sometimes called the wilcoxon rank sum test is used to compare the differences between two samples when the sample distributions are not normally distributed and the sample sizes are small n 30. Sometimes called u test wilcoxon test or mann whitney test named after the statisticians who contributed to its development. An advantage with this test is that the two samples under consideration do not necessarily need to have the same number of observations or instances.
Freidlin gastwirth 2000 advocate the retirement of the median test from general use being replaced by the wilcoxon mann whitney and related tests.
When the two distributions have a similar shape you can use the test to compare also the medians. An advantage with this test is that the two samples under consideration do not necessarily need to have the same number of observations or instances. Hart 2001 notes that the wilcoxon mann whitney test is a test of both location and shape not as most researchers consider it a test of difference between medians. Sometimes called u test wilcoxon test or mann whitney test named after the statisticians who contributed to its development.
