means
Factorial ANOVA
Estimate main effects and interactions for multiple categorical factors.
Requirements
- continuous outcome
- two or more factors
Avoid when
- sparse cells
- many unplanned interactions
Formula
y = μ + α + β + αβ + ε
Interpretation
Separates factor main effects from interaction terms.
Worked example
Estimate treatment, sex, and treatment-by-sex effects on a continuous outcome.
Open example datasets