## 2. How many categories are there?

- There is one set of categories, so a one-way classification including a test of homegeneity is appropriate: One-way Chi-square test (non-parametric test only)
- There are two sets of categories, so a two-way test is appropriate (also called a 'test of association' or a 'test of independence'): Two-way Chi-square test (non-parametric test only)