| 变量 | TFP_OP |
| Digit | 0.113*** |
| (7.203) | |
| lnenter-age | 0.006*** |
| (4.852) | |
| lnasset | 0.467*** |
| (101.065) | |
| lev | 0.342*** |
| (14.094) | |
| roa | 0.028*** |
| (4.574) | |
| lnboar | −0.264*** |
| (−8.662) | |
| 常数项 | −3.394*** |
| (−31.807) | |
| 固定效应 | YES |
| Observations | 13,816 |
| R-Squared | 0.884 |