| Variables in the model | k |
| R2 |
| nothing | 1 | 10.9629 | 0.0000 |
| x1 | 2 | 4.0079 | 0.7105 |
| x2 | 2 | 8.0285 | 0.3830 |
| x3 | 2 | 9.8973 | 0.4681 |
| x4 | 2 | 11.8750 | 0.1164 |
| x1·x2 | 3 | 3.9590 | 0.7215 |
| x1·x3 | 3 | 5.4301 | 0.6860 |
| x1·x4 | 3 | 3.9636 | 0.7212 |
| x2·x3 | 3 | 8.0913 | 0.5470 |
| x2·x4 | 3 | 6.5918 | 0.4576 |
| x3·x4 | 3 | 6.6577 | 0.6098 |
| x1·x2·x3 | 4 | 6.1331 | 0.6701 |
| x1·x2·x4 | 4 | 7.3275 | 0.5937 |
| x1·x3·x4 | 4 | 5.4875 | 0.7011 |
| x2·x3·x4 | 4 | 4.0022 | 0.7410 |
| x1·x2·x3·x4 | 5 | 4.0246 | 0.7704 |
