(a)

(b)

(c)

dlRD_assets

lRD_assets

lRD_assets

L.inde_com

0.135

0.785***

0.785***

(0.55)

(3.03)

(3.03)

L.log_Total

−0.0720***

−0.114***

−0.114***

(−5.51)

(−3.14)

(−3.14)

L.cap_exp

−0.112

−0.266

−0.266

(−0.49)

(−1.52)

(−1.52)

L.Leverage

0.00161

0.00164

0.00164

(0.79)

(1.24)

(1.24)

L.Borad_size

0.0143*

0.0230**

0.0230**

(1.67)

(2.11)

(2.11)

L.logQ

0.100***

0.0305***

0.0305***

(10.80)

(3.45)

(3.45)

_cons

−3.132***

−2.382***

−93.38***

(−9.94)

(−3.05)

(−4.28)

N

4598

4598

4598

r2

0.0481

0.0198

0.0198

Year fixed effects

Yes

Yes

Yes

Firm fixed effects

No

Yes

Yes

Trend control

No

No

Yes