变量

模型(1)

模型(2)

模型(3)

模型(4)

模型(5)

HL

6.051^***

(3.11)

5.632^**

(2.20)

5.710^**

(2.56)

5.656^***

(2.91)

IL

−6.850^***

(−3.42)

−9.908^***

(−3.57)

−8.103^***

(−3.87)

−6.364^***

(−3.17)

HL²

−13.440

(−1.13)

IL²

22.379

(1.50)

HL × IC

24.578^*

(1.88)

IL × IC

−29.931^**

(−2.07)

HL² × IC

IL² × IC

HL × EU

10.701^**

(2.29)

IL × EU

−11.267^**

(−2.37)

HL² × EU

IL² × EU

CONTROLS

YES

YES

YES

YES

YES

F

9.40^***

1.14^**

1.61^*

1.58^**

1.59^**

R²

0.0223

0.0129

0.0167

0.0217

0.0240

N

640

640

640

640

640

YEAR

YES

YES

YES

YES

YES

IND

YES

YES

YES

YES

YES