Variable

(1)

(2)

(3)

(4)

lnRD

lnRD

lnRD

lnRD

lnSub

0.2989***

0.0453*

0.0377**

0.0268**

(5.1931)

(1.8208)

(2.0725)

(2.0230)

Roe

1.7278**

−0.3364

(2.2561)

(−0.5072)

Size

1.0244***

0.7012***

(31.4565)

(7.9101)

Top1

0.0035

0.0066

(1.0901)

(1.1486)

DPR

0.0089**

−0.0184**

(2.0649)

(−2.5864)

F_leve

−0.0114

−0.0085

(−0.2949)

(−0.3026)

O_leve

0.0929***

−0.0371*

(3.0137)

(−1.7982)

HHI_A

−2.4249***

−14.4411***

(−3.4200)

(−3.0624)

Constant

14.0147***

−4.5952***

16.8616***

6.2229**

(16.5427)

(−7.0749)

(50.2848)

(2.2895)

N

561

561

561

561

R-squared

0.2215

0.9056

0.5987

0.7219

firm

no

no

yes

yes

year

no

no

yes

yes

Number of stkcd

99

99

99

99