Sulfur dioxide emission intensity

lnSI

Industrial soot emission intensity

lnMI

OLS

RE

FE

OLS

RE

FE

Independent variable

Policy_t

0.0760

(0.45)

−0.1181

(−1.59)

−0.7628

(−1.36)

0.9801***

(3.18)

0.5679***

(2.74)

0.6305

(0.62)

YRD_i × Policy_t

−0.3996***

(−2.70)

−0.0660

(−0.86)

−0.0678

(−0.79)

−0.4817*

(−1.76)

−0.2599

(−1.14)

−0.3065

(−1.32)

PRD_i × Policy_t

−0.7107***

(−3.25)

−0.0913

(−0.72)

−0.0716

(−0.59)

−1.1798***

(−3.25)

−0.2818

(−0.96)

−0.2058

(−0.69)

Control variable

lnPGDP_it

−0.2000

(−0.90)

−0.3008**

(−1.98)

−0.3224

(−1.63)

−0.1632

(−0.57)

−0.6337***

(−4.40)

−0.8490***

(−4.46)

lnSTR_it

1.4267***

(4.16)

1.8547***

(4.86)

1.5978***

(3.45)

1.2943**

(2.21)

1.6584***

(2.76)

1.6840**

(2.41)

lnPOP_it

−0.2483

(−1.51)

−0.1954

(−0.98)

−0.5333

(−1.23)

−0.3544*

(−1.74)

−0.4428*

(−1.86)

−0.9603

(−1.18)

lnUR_it

0.1678

(1.48)

−0.1254**

(−2.32)

−0.2360***

(−3.83)

−0.0090

(−0.07)

−0.0819

(−0.57)

−0.1912

(−1.03)

lnSC_it

0.0103

(0.08)

−0.0354

(−0.63)

−0.0173

(−0.30)

−0.2495

(−1.48)

−0.1194

(−1.38)

−0.1537

(−1.52)

lnFE_it

−0.2460**

(−2.03)

−0.3087**

(−2.55)

−0.0142

(−0.06)

−0.1820

(−1.25)

0.0775

(0.54)

0.2174

(0.57)

lnRD_it

−0.1750***

(−2.73)

−0.0969***

(−3.29)

−0.0832*

(−1.75)

−0.1240*

(−1.68)

−0.1168***

(−2.87)

−0.0427

(−0.50)

lnFI_it

−0.0834

(−0.97)

0.0167

(0.34)

−0.0364

(−0.72)

−0.1065

(−0.90)

−0.0696

(−1.00)

−0.0662

(−0.86)