ERIC Number: ED091423
Record Type: Non-Journal
Publication Date: 1974-Apr
The ANOVA F-Test Versus The Kruskal-Wallis Test: A Robustness Study.
Feir, Betty J.; Toothaker, Larry E.
Researchers are often in a dilemma as to whether parametric or nonparametric procedures should be cited when assumptions of the parametric methods are thought to be violated. Therefore, the Kruskal-Wallis test and the ANOVA F-test were empirically compared in terms of probability of a Type I error and power under various patterns of mean differences in combination with patterns of variance inequality, and patterns of sample size inequality. The Kruskal-Wallis test was found to be competitive with the ANOVA F-test in terms of alpha but not for power. Power of the Kruskal-Wallis test was grossly affected in all but one situation for nonstepwise mean differences when sample sizes and variances were negatively related and when small levels of significance were utilized. The ANOVA F-test, however, was found to be generally robust for the types of specified mean differences. (Author)
Publication Type: Speeches/Meeting Papers
Education Level: N/A
Authoring Institution: N/A