Median test
From Wikipedia, the free encyclopedia
In statistics, Mood's median test is a special case of Pearson's chi-square test. It tests the null hypothesis that the medians of the populations from which two samples are drawn are identical. The data in each sample are assigned to two groups, one consisting of data whose values are higher than the median value in the two groups combined, and the other consisting of data whose values are at the median or below. A Pearson's chi-square test is then used to determine whether the observed frequencies in each group differ from expected frequencies derived from a distribution combining the two groups.
The test has low power (efficiency) and is largely regarded as obsolete. The Wilcoxon-Mann-Whitney U two-sample test should be considered instead.
[edit] References
- Friedlin, B. & Gastwirth, J. L. (2000). Should the median test be retired from general use? The American Statistician, 54, 161-164.
