| 替换变量法 | 延长窗口观测期 | 替换固定效应 | |||
| (1) | (2) | (3) | (4) | (5) | (6) |
变量 | TFP_OP | TFP | TFP | TFP | TFP | TFP |
DCG | 0.012*** |
| 0.017*** | 0.010** | 0.021*** | 0.011*** |
| (2.89) |
| (4.04) | (2.30) | (4.85) | (2.67) |
DIGI |
| 0.100*** |
|
|
|
|
|
| (4.67) |
|
|
|
|
控制变量 | YES | YES | YES | YES | YES | YES |
个体固定效应 | YES | YES | YES | YES | NO | YES |
年度固定效应 | YES | YES | YES | YES | YES | YES |
行业固定效应 | NO | NO | NO | NO | YES | NO |
行业*年度固定效应 | NO | NO | NO | NO | NO | YES |
Observations | 11,220 | 11,220 | 10,098 | 8976 | 11,220 | 11,210 |
R-squared | 0.920 | 0.941 | 0.944 | 0.948 | 0.763 | 0.946 |