Equivalence of Population Variances: Synchronizing the Objective and Analysis |
| |
| Authors: | Constance A Mara |
| |
| Institution: | Behavioral Medicine and Clinical Psychology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA |
| |
| Abstract: | Researchers are often interested in establishing equivalence of population variances. Traditional difference-based procedures are appropriate to answer questions about differences in some statistic (e.g., variances, etc.). However, if a researcher is interested in evaluating the equivalence of population variances, it is more appropriate to use a procedure designed to determine equivalence. A simulation study was used to compare novel equivalence-based tests to traditional variance homogeneity tests under common data conditions. Results demonstrated that traditional difference-based tests assess equality of variances from the wrong perspective and that the proposed Levene-Wellek-Welch test for equivalence of group variances the best performing test for detecting equivalence. An R function is provided in order to facilitate use of this test for equivalence of population variances. |
| |
| Keywords: | ANOVA dispersion equivalence testing homogeneity of variances |
|
|
