| 变量 | (1) | (2) | (3) | (4) |
| CNI | CNPI | CNEI | CNDI | |
| DID | ||||
| ( | ( | ( | ( | |
| GDP | 0.0070 | |||
| ( | ( | (1.943) | ( | |
| INNOV | 0.0021 | 0.0057 | 0.0061 | 0.0107 |
| (0.931) | (2.960) | (5.308) | (5.585) | |
| PM25 | 0.0200 | 0.0136 | ||
| ( | (2.804) | ( | (2.164) | |
| INDUS | ||||
| ( | ( | ( | ( | |
| 常数项 | 0.4459 | 0.2609 | 0.1232 | 0.5471 |
| (5.950) | (5.017) | (3.259) | (11.972) | |
| 样本量 | 3,520 | 3,520 | 3,520 | 3,520 |
| 0.836 | 0.820 | 0.944 | 0.717 | |
| 年份固定 | 是 | 是 | 是 | 是 |
| 城市固定 | 是 | 是 | 是 | 是 |