| Factor | Estimated value | Statistic t | Prob. > t |
| M | 1.630 | 0.00025 | 0.000 |
| B | 0.018 | 0.00025 | 0.009 |
| C | 0.008 | 0.00025 | 0.020 |
| D | 0.008 | 0.00025 | 0.021 |
| B*C | −0.006 | 0.00025 | 0.027 |
| B*D | 0.008 | 0.00025 | 0.019 |
| C*D | 0.012 | 0.00025 | 0.014 |