Published Online: 30 JAN 2010
Copyright © 2010 John Wiley & Sons, Inc. All rights reserved.
Corsini Encyclopedia of Psychology
How to Cite
McKight, P. E. and Najab, J. 2010. Kruskal-Wallis Test. Corsini Encyclopedia of Psychology. 1.
- Published Online: 30 JAN 2010
The Kruskal-Wallis (Kruskal & Wallis, 1952) is a nonparametric statistical test that assesses the differences among three or more independently sampled groups on a single, non-normally distributed continuous variable. Non-normally distributed data (e.g., ordinal or rank data) are suitable for the Kruskal-Wallis test. In contrast, the one-way analysis of variance (ANOVA), which is a parametric test, may be used for a normally distributed continuous variable. The Kruskal-Wallis test is an extension of the two-group Mann-Whitney U (Wilcoxon rank) test. Thus, the Kruskal-Wallis is a more generalized form of the Mann-Whitney U test and is the nonparametric version of the one-way ANOVA.