(4)

(5)

(6)

东部

西部

托宾Q

托宾Q

托宾Q

RD

0.151***

0.167***

−0.00553

(4.077)

(4.106)

(−0.123)

MI

0.0499

0.0344

0.0610

(1.533)

(0.523)

(1.217)

Age

0.00832

−0.000450

0.0479**

(0.987)

(−0.046)

(2.542)

Lev

−1.397**

−1.236*

−1.815***

(−2.550)

(−1.654)

(−4.555)

cash

2.162***

2.022**

2.195*

(2.660)

(2.040)

(1.897)

size

−0.750***

−0.768***

−0.722***

(−6.625)

(−5.436)

(−8.587)

_cons

18.89***

19.49***

17.88***

(8.692)

(7.185)

(9.795)

N

2285

1753

532

adj.R-sq

0.270

0.253

0.413

r2

0.272

0.256

0.420

F

121.0

102.6

46.21