A trend test is a chi-square test that checks whether frequencies in a categorical variable change systematically across ordered groups or over time. section 5.2.3
It addresses pattern questions rather than simply asking whether categories differ, making it useful when group order or time provides meaningful structure. section 5.2.3
Distinguish it from related chi-square tests:
- Goodness-of-fit tests compare one sample’s observed frequencies with expected frequencies. section 5.2.3
- Tests of independence compare observed and expected frequencies between two categorical variables. section 5.2.3
- Trend tests focus on systematic change across ordered groups or time. section 5.2.3
The treatment names the test’s purpose but does not provide its calculation, implementation procedure, assumptions, or a worked trend-test example. section 5.2.3
