1. Two Factor ANOVA with 1 Unit per Treatment
KNNL – Chapter 20

2. One Observation per Cell of 2-Way Table
When n=1, the overall sample size is nT = ab(1)=ab
For the interaction model, each observation is equal to its fitted value (each observation is its cell mean)
No problems when the additive (no interaction) model is fit
The “error sum of squares” is equivalent to interaction sum of squares for the additive model
We can test whether there is an interaction only if it takes on some specific form such as: (ab)ij = Daibj
We can test whether D=0 based on Tukey’s One Degree of Freedom for Non-Additivity Test (ODOFNA)

3. Additive Model

4. Tukey’s Test for Additivity