What does a Tukey test tell us?
Tukey’s test compares the means of every treatment to the means of every other treatment; that is, it applies simultaneously to the set of all pairwise comparisons: Ui – Uj and identifies any difference between two means that is greater than the expected standard error.
What is the difference between ANOVA and Tukey test?
NOTE: The Tukey test is a weaker statistical test than the ANOVA. What this means is that an ANOVA might show a statistically significant difference with a p-value relatively close to the alpha, but the Tukey difference table might not have any differences which are greater than the minimum difference (Dmin).
What does P adj mean in R?
p-value adjusted for multiple comparisons
p adj is the p-value adjusted for multiple comparisons using the R function TukeyHSD() . For more information on why and how the p-value should be adjusted in those cases, see here and here. Yes you can interpret this like any other p-value, meaning that none of your comparisons are statistically significant.
What could the Tukey’s honestly significant differences HSD be used for?
The Tukey’s honestly significant difference test (Tukey’s HSD) is used to test differences among sample means for significance. The Tukey’s HSD tests all pairwise differences while controlling the probability of making one or more Type I errors.
How does the Fisher’s least significant difference test differ from Tukey’s honestly significant difference test?
Re: Topic 6 DQ 2 Turkey’s honestly significant difference test is the most conservative while Fisher’s least significant difference test is the most liberal. Fisher’s test is also called the protected t test, the number of people in each group could be different.
When would you use the Tukey HSD or the Tukey Kramer test and why?
The Tukey test is invoked when you need to determine if the interaction among three or more variables is mutually statistically significant, which unfortunately is not simply a sum or product of the individual levels of significance.