Pairwise t-test
- we have $n$ groups, $n > 2$
- we conduct a series of Two-Sample t-tests to find out which groups are different
- e.g. in post-ANOVA analysis
It's important to modify $\alpha$ to avoid Type I Errors
- when we run many tests, it's inevitable that we make them just by chance
E.g. use Bonferroni Correction
- use modified confidence level $\alpha^* = \alpha \cdot \cfrac{1}{K}$
- where for $k$ groups $K= \cfrac{k \cdot (k - 1)}{2}$
Sources