| Variables | Parameters | Standard error | t-test |
| x1 | −56.65 | 16.43 | −3.45 |
| x2 | −0.75 | 7.87 | −0.10 |
| x3 | 232.76 | 89.52 | 2.60 |
| x1z1 | 11.37 | 20.02 | 0.57 |
| x2z1 | 17.46 | 20.02 | 0.87 |
| x3z1 | −4.35 | 9.64 | −0.45 |
| x1z2 | −3.37 | 9.64 | −0.35 |
| x2z2 | 29.79 | 109.64 | 0.27 |
| x3z2 | −77.35 | 109.64 | −0.71 |