A post hoc test is warranted when one:
A) rejects the null hypothesis and there are more than two groups.
B) fails to reject the null hypothesis in an ANOVA.
C) rejects the null hypothesis when performing an independent-groups t test.
D) has an a priori prediction about which group means will differ.

Question

Quizplus · Accepted Answer

A post hoc test is used after rejecting the null hypothesis in an analysis of variance (ANOVA) when there are more than two groups to compare. This is because ANOVA tells us only that at least two groups differ, but not which specific groups are different from each other. Post hoc tests are designed to make these specific comparisons.

A Post Hoc Test Is Warranted When One