What is Tukey correction?
Tukey’s multiple comparison test is one of several tests that can be used to determine which means amongst a set of means differ from the rest. The test compares the difference between each pair of means with appropriate adjustment for the multiple testing.
Is the Bonferroni correction a post hoc test?
A Bonferroni test is perhaps the simplest post hoc analysis. A Bonferroni test is a series of t-tests performed on each pair of groups. As we discussed earlier, the number of groups quickly grows the number of comparisons, which inflates Type I error rates.
How is the Tukey HSD different from the Bonferroni test?
The detailed answer is that the Tukey HSD is a proper “post hoc” test whereas the Bonferroni test is for planned comparisons. The Bonferroni test also tends to be overly conservative, which reduces its statistical power.
When to use the Bonferroni post hoc test?
The Bonferroni Method. The Bonferroni post-hoc test should be used when you have a set of planned comparisons you would like to make beforehand. For example, suppose we have three groups – A, B, C – and we know ahead of time that we’re only interested in the following comparisons: μ A = μ B; μ B = μ C
How does the Bonferroni method control the family error rate?
Alternatively, the Bonferroni method does control the family error rate, by performing the pairwise comparison tests using α / g level of significance, where g is the number of pairwise comparisons. Hence, the Bonferroni confidence intervals for differences of the means are wider than that of Fisher’s LSD.
How is the Bonferroni approach compared to the Dunnett procedure?
We can compare the Bonferroni approach to the Dunnett procedure. The Dunnett procedure calculates the difference of means for the control versus treatment one, control versus treatment two, etc. to a – 1. Which provides a – 1 pairwise comparisons.