| influencing factor | variable | customs brokerage | flight transportation | trucking |
| u2 | u3 | u1 | ||
| customs brokerage service | u2 | 1 | 3 | 5 |
| flight transportation service | u3 | 0.33 | 1 | 3 |
| trucking service | u1 | 0.20 | 0.33 | 1 |