| (1) | (2) | (3) | (4) | (5) | (6) | |
变量 | RD1 | RD1 | RD2 | RD2 | RD3 | RD3 | |
Dul = 1 | Dul = 0 | Dul = 1 | Dul = 0 | Dul = 1 | Dul = 0 | ||
常数项 | 0.344 | 2.164*** | 0.136*** | 0.142*** | 0.080*** | 0.078*** | |
| (0.658) | (5.673) | (8.651) | (17.312) | (11.224) | (20.221) | |
Academic | 0.568*** | 0.484*** | 0.016*** | 0.013*** | 0.008*** | 0.006*** | |
| (20.842) | (16.816) | (19.490) | (20.360) | (20.956) | (21.136) | |
Size | 0.666*** | 0.644*** | −0.006*** | −0.005*** | −0.004*** | −0.004*** | |
| (42.853) | (55.100) | (−11.761) | (−20.153) | (−18.926) | (−29.776) | |
Lev | −0.239*** | −0.428*** | −0.031*** | −0.029*** | 0.001 | −0.001* | |
| (−3.051) | (−6.993) | (−13.234) | (−21.776) | (1.153) | (−1.935) | |
ROA | 1.935*** | 2.326*** | −0.039*** | −0.021*** | 0.038*** | 0.033*** | |
| (8.567) | (12.419) | (−5.777) | (−5.349) | (12.333) | (17.471) | |
Growth | 0.017 | 0.051* | −0.002 | −0.001 | −0.000 | 0.000 | |
| (0.489) | (1.881) | (−1.574) | (−0.891) | (−1.026) | (0.920) | |
Board | 0.015 | 0.010 | −0.006** | −0.003** | −0.000 | 0.000 | |
| (0.181) | (0.171) | (−2.255) | (−2.377) | (−0.220) | (0.105) | |
Indep | 0.320 | −0.898*** | 0.013 | 0.001 | 0.009** | −0.006*** | |
| (1.174) | (−4.005) | (1.620) | (0.114) | (2.325) | (−2.697) | |
FirmAge | −0.316*** | −0.465*** | −0.008*** | −0.011*** | −0.003*** | −0.004*** | |
| (−8.898) | (−15.461) | (−7.623) | (−16.744) | (−5.253) | (−14.386) | |
Age | 0.173** | 0.044 | 0.001 | 0.001 | 0.000 | 0.001* | |
| (1.961) | (0.658) | (0.312) | (0.603) | (0.043) | (1.762) | |
Gender | 0.042 | 0.038 | 0.001 | 0.000 | 0.001 | 0.001*** | |
| (0.830) | (0.874) | (0.725) | (0.101) | (1.177) | (3.171) | |
Degree | 0.061*** | 0.051*** | 0.003*** | 0.002*** | 0.001*** | 0.001*** | |
| (4.419) | (4.527) | (7.240) | (10.214) | (7.157) | (7.259) | |
Site | 0.090*** | 0.153*** | 0.002*** | 0.002*** | 0.001*** | 0.001*** | |
| (5.774) | (14.830) | (5.057) | (10.867) | (6.228) | (13.252) | |
Ind/Year | 控制 | 控制 | 控制 | 控制 | 控制 | 控制 | |
Adjusted R-squared | 0.517 | 0.409 | 0.334 | 0.347 | 0.317 | 0.332 | |
F | 120.6 | 198.0 | 56.98 | 152.6 | 52.80 | 142.5 | |
N | 4472 | 11676 | 4472 | 11676 | 4472 | 11676 | |
系数差异 | 0.84*** | 0.003*** | 0.002*** | ||||
Chi2 | 6.88 | 8.66 | 10.44 | ||||
P-Value | 0.0087 | 0.0033 | 0.0012 |