Why is a post-hoc test necessary if you've used a one-way ANOVA to avoid the problem of multiple comparisons?
A) Accounting for their respective standard deviations increased the alpha level.
B) In the case of a significant F value, you were unsure of how the three groups differed.
C) It was necessary to set a new error rate for each individual t-test.
D) All these are correct.

Question

Quizplus · Accepted Answer

A post-hoc test is necessary after a one-way ANOVA to determine which groups differ significantly from each other. This is because the ANOVA only tells you that there is a significant difference between the groups, but it does not tell you which groups are different. A post-hoc test allows you to compare the means of the different groups and determine which groups are significantly different from each other.

Why Is a Post-Hoc Test Necessary If You've Used a One-Way