Next section: Sign test

Rank randomization tests are also available for correlation and for testing differences between more than two groups (analogous to one-way ANOVA). The rank randomization test for correlation is called Spearman's rho. The rank randomization test for differences among groups is called the Kruskal and Wallis Test. In summary, rank randomization tests are based on the principle of randomization. They are much easier to compute than randomization tests. However, they are less powerful than randomization tests and the more typically performed parameteric tests such as analysis of variance. For this reason, they are not as widely used.

Next section: Sign test