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 |