Question

Explain how analysis of variance (ANOVA) could be used to test a study hypothesis

Answer 1

In ANOVA testing we try to find out whether there exists a difference in the means between groups. An example of such a study is:

Students from 3 universities take an exam and we want to check if one University is better than the others or their scores are the same.

So our hypothesis in this case would be:

H0: u1=u2=u3 vs H1: u1 not equal u2 not equal u3

ANOVA testing only tells whether our test is significant ie whether there is a difference in the means of the different groups. It does not tell us which mean is different from the rest.

The assumptions needed to carry out the test are:

1. The data should come from a normal distribution

2. The sample must be chosen randomly

3. There must be homogeneity of variance among the groups.