ANOVA Flashcards
ANOVA
Analysis of Variance is a statistical method used to test differences between two or more means. Used to test general rather than specific differences among means (inferences about means are made by analyzing variance).
Helpful for testing three or more variables. It is similar to two multiple two-sample t-tests, however, results in fewer type 1 errors and is appropriate for a range of issues. ANOVA groups difference by comparing the means of each group and includes spreading out the variances into diverse sources.
ANOVA - Why is a Post Hoc done?
The null states there is no difference between at least one group in the analysis. In order to compare a specific group in the analysis, a post hoc test should be conducted.
The most common is a Bonferroni - level of significance is 0.05, which is divided by the number of t-tests to be done. Most conservative post-hoc = less likely to yield a significant result.
