变量

(1)

(2)

(3)

(4)

lndebt

0.1777657^***

0.1243932^*

0.1619269^**

0.1898394^***

(3.04)

(1.96)

(2.71)

(3.13)

lnur

1.225003^***

1.072308^**

0.9529607^*

(2.91)

(2.04)

(1.83)

lnw

−0.2224447

−0.6180282^***

−0.8198878^***

(−1.59)

(−2.98)

(−3.61)

lnfdi

0.1921697^***

0.1740378^***

(4.05)

(3.74)

lnpatent

0.1438525^**

(2.25)

Cons

−2.929008^***

−1.902315^***

−2.79712^***

−3.057842^***

(−5.91)

(−3.60)

(−5.68)

(−5.95)

N

210

210

210

210

R²

0.0803

0.1486

0.202

0.2361