| 
 | 
 | 固定效应(FE) | 无固定效应 | ||
| 
 | OLS | 时间固定 | 空间固定 | 时空固定 | |
| lnict | −0.286 | 0.211 | 0.263* | 0.3007** | 0.1751 | 
| 
 | (0.2257) | (0.1774) | (0.0723) | (0.0403) | (0.261) | 
| lnpgdp | 2.2393*** | 0.2197*** | 1.5137*** | 0.2696*** | 0.1632** | 
| 
 | (0.0000) | (0.0055) | (0.0005) | (0.0011) | (0.036) | 
| ln2pgdp | −0.2507* | −0.7949* | 0.2982** | −0.8488** | −0.5080 | 
| 
 | (0.0886) | (0.0501) | (0.0141) | (0.0337) | (0.202) | 
| lnope | −0.00610 | 0.0328** | 0.1657*** | 0.0291** | 0.0322** | 
| 
 | (0.8071) | (0.0172) | (0.0000) | (0.0364) | (0.024) | 
| lneg | 0.4043*** | 0.0398** | 0.3194*** | 0.0410** | 0.0407** | 
| 
 | (0.0000) | (0.0163) | (0.0000) | (0.0171) | (0.023) | 
| lnurb | −1.0222** | 1.7460*** | −3.6968*** | 1.7159*** | 1.3715*** | 
| 
 | (0.0187) | (0.0000) | (0.0000) | (0.0001) | (0.001) |