| Sample sizes | Normal Exogenous Variables | Uniform Exogenous Variables | ||
| Exact | Over | Exact | Over | |
| 10 | OLS\2SLS | FIML | OLS | 2SLS |
| 20 | 2SLS | FIML | OLS | 2SLS\3SLS |
| 30 | OLS | 2SLS | OLS | 2SLS |
| 50 | 2SLS | 2SLS | 2SLS | FIML |
| 100 | 2SLS | 2SLS\3SLS | 2SLS | 2SLS |
| 250 | 3SLS | 2SLS\3SLS | OLS | FIML |
| 500 | 3SLS | FIML | 2SLS | 2SLS\FIML |