| 模型1 | 模型2 | 模型3 | 模型4 |
RDI | 40464317.8* | 0.0391*** | 291232356.1*** | 0.0796*** |
(1.82) | (3.70) | (4.16) | (3.35) | |
Firm size | 987741222.7*** | −0.210*** | 1.43664e+09*** | −0.225*** |
(19.61) | (−8.36) | (17.88) | (−8.25) | |
Debt ratio | −2.37307e+09*** | −0.890*** | −3.96644e+09*** | −0.876*** |
(−6.53) | (−4.66) | (−7.03) | (−4.58) | |
TAT | 273743321.3 | 0.080 | 526061667.1** | 0.0822 |
(1.55) | (0.90) | (2.00) | (0.92) | |
Cash | 243123773.4 | 0.663** | 1.41E+09 | 0.633* |
(0.38) | (2.02) | (1.46) | (1.93) | |
TAG | 642131830.3* | 0.111 | −28187930.9 | 0.103 |
(1.84) | (0.67) | (−0.06) | (0.62) | |
Duality | 211233755.6 | −0.157* | 579603100.8** | −0.146 |
(1.24) | (−1.66) | (2.07) | (−1.54) | |
OBH | −179065742.9* | 0.0146 | 22812222.6 | 0.0753 |
(−1.83) | (0.28) | (0.10) | (1.02) | |
OC |
|
| 5.91870e+09*** | 0.757** |
|
| (5.23) | (1.97) | |
RDIoc |
|
| −875810620.9*** | −0.119* |
|
| (−4.75) | (−1.90) | |
cons | −2.19247e+10*** | 7.578*** | −3.52561e+10*** | 7.479*** |
(−18.53) | (12.63) | (−19.75) | (12.37) | |
N | 1030 | 1030 | 1030 | 1030 |
年度虚拟变量 | 控制 | 控制 | 控制 | 控制 |
行业虚拟变量 | 控制 | 控制 | 控制 | 控制 |
Adj-R-Squared | 0.4255 | 0.514 | 0.4791 | 0.4899 |