(1)

(2)

(3)

全样本

东部

中西部

截距

−109.368^*

−74.294

−197.400^**

IE

4.422^*

14.727^*

12.574^*

Ln(size)

23.843^*

18.715^*

35.317^**

pb

8.053^**

8.163^**

6.210^**

np

0.056

0.098^*

0.163^*

tret

1.179

1.88

−1.377

lev

−0.615^*

−0.598^*

−0.298

R²

0.954

0.988

0.928

R² (within)

0.957

0.964

0.854

F

313.652

27.021

62.528

检验

p = 0.000

p = 0.000

p = 0.000