Levene’s Homogeneity of Variance Test

Homogeneity of variance (HOV) is one of the assumptions of some frequently used statistical procedures for group mean comparisons, such as a one-way analysis of variance (ANOVA) or an independent-samples t test. Under the HOV assumption, population variances of all groups are assumed to be equal. That is, the null hypothesis (H0) being tested for verifying the HOV assumption is that the population variances across groups are equal; that is, ${\text{H}}_0:{\sigma }_1^2={\sigma }_2^2={\sigma }_3^2=\text{. . .}={\sigma }_k^2$, where k denotes the number of groups compared in a study.

The examination of the HOV assumption is always an essential step before conducting a comparison of group means using ANOVAs or t tests. Violations of the HOV assumption may result in misleading results in terms of the test for differences in group means. Levene’s ...