In an ANOVA test, when the null hypothesis is rejected, we know that at least one of the means is significantly different from the others. In order to find out which mean(s) are significantly different, we must conduct a________.
A) t test.
B) post hoc test.
C) post mortem test.
D) chi square test.

Question

Quizplus · Accepted Answer

When the null hypothesis is rejected in an ANOVA test, we know that at least one of the means is significantly different from the others. However, we do not know which mean(s) are significantly different. A post hoc test is necessary to compare individual means and determine which ones are significantly different from each other. Option A (t test) is incorrect because t tests are used to compare the means of two groups, not multiple groups as in an ANOVA. Option C (post mortem test) is not a valid statistical test. Option D (chi square test) is used to test independence between categorical variables, so it is not relevant for comparing means.

In an ANOVA Test, When the Null Hypothesis Is Rejected