(1) OLS

(2) FE

(3) RE

(4) FE_TW

VARIABLES

lnco₂

lnco₂

lnco₂

lnco₂

digtra

0.131

−0.121**

−0.122**

−0.154***

(1.16)

(−2.18)

(−2.32)

(−2.80)

lntech

−0.261***

0.053**

0.044*

0.057**

(−3.65)

(2.01)

(1.71)

(2.09)

lneco

0.543***

0.216***

0.247***

−0.250*

(3.18)

(3.19)

(3.92)

(−1.80)

lnpopu

−0.100

−0.055

−0.269**

0.554

(−0.95)

(−0.17)

(−2.32)

(1.60)

open

−0.356

0.101

0.018

0.044

(−1.43)

(0.87)

(0.17)

(0.37)

industry

2.792***

0.218

0.383

0.549*

(4.92)

(0.80)

(1.46)

(1.79)

service

0.087

−0.315**

−0.294**

−0.381**

(0.15)

(−2.33)

(−2.27)

(−2.20)

2015.year

0.011

(0.51)

2016.year

0.034

(1.05)

2017.year

0.092**

(2.09)

2018.year

0.143**

(2.48)

2019.year

0.187***

(2.79)

Constant

3.184

4.284*

5.740***

4.166*

(1.65)

(1.72)

(5.38)

(1.72)

Observations

180

180

180

180

R-squared

0.347

0.217

0.312

Numberofid

30

30

30