- Analysis of Variance
also referred to as ANOVA, is a method of testing whether or not the means of three or more populations are equal. The method is applicable if:
- all populations of interest are normally distributed.
- the populations have equal standard deviations.
- samples (not necessarily of the same size) are randomly and independently selected from each population.
The test statistic for analysis of variance is the \(F\)-ratio.
- Between-Groups Variance
an estimate of the average variance among sample means (i.e., from the different groups) across all of the groups.
- One-Way ANOVA
an analysis of variance with one independent (grouping) variable.
- Within-Groups Variance
an estimate of the average of the sample variances (i.e., within the different groups) across all of the groups.