Is The One Way Anova Test Robust. The sample means must all be equal. Anova is fairly robust in terms of the error rate when sample sizes are equal.
As regards the normality of group data the one way anova can tolerate data that is non normal skewed or kurtotic distributions with only a small effect on the type i error rate. However if the sample sizes are not the same and this assumption is severely violated you could instead run a kruskal wallis test which is the non parametric version of the one way anova. Is the test robust.
What are the requirements to perform a one way anova.
The sample means must all be equal. The data are assumed to be symmetrically distributed apart from some outliers although the assumption of normality may be violated. The test statistic to be used is a weighted sum of squares similar to the welch 1951. Is the test robust.
