Permanent Note Created: 01-10-2022 12:47
An interaction between A and B when predicting C is specified as:
| A | B | C | |
|---|---|---|---|
| A | 0 | 0 | 0 |
| B | 0 | 0 | 0 |
| C | 1 | 1 | 0 |
Each row in the interaction matrix is either all zeros or has at least two ones. Having to ones means there is a two-way interaction. It is also possible to have a three way interaction which would have three ones. In that case all two way interactions need to be specified in the model also.
graph LR;
A-->{ }-->C;
W-->{ }--C;