Table 4.
Model setting test.
| Test method | H0 | Statistical indicators | Statistics | P-value | Outcome | |
|---|---|---|---|---|---|---|
| SO2 data model | F Test | Choose mixed regression | F(29, 324) | 73.02 | 0.0000 | Reject mixed regression, choose fixed effect model |
| LM Test | Choose mixed regression | chibar2(01) | 1,073.03 | 0.0000 | Reject mixed regression model and choose random effect model | |
| Hausman Test | Choose random regression | chi2(7) | 36.90 | 0.0001 | Reject random effect model, choose fixed effect model | |
| PGDP date model | F Test | Choose mixed regression | F(29, 324) | 80.09 | 0.0000 | Reject mixed regression, choose fixed effect model |
| LM Test | Choose mixed regression | chibar2(01) | 1,201.35 | 0.0000 | Reject mixed regression model and choose random effect model | |
| Hausman Test | Choose random regression | chi2(7) | 18.39 | 0.0103 | Reject random effect model, choose fixed effect model | |
| Total data model | F Test | Choose mixed regression | F(29, 323) | 83.79 | 0.0000 | Reject mixed regression, choose fixed effect model |
| LM Test | Choose mixed regression | chibar2(01) | 1,209.08 | 0.0000 | Reject mixed regression model and choose random effect model | |
| Hausman Test | Choose random regression | chi2(7) | 23.11 | 0.0032 | Reject random effect model, choose fixed effect model |