Table 5.

Spillover effects

Treatment group	AQI
	Locked cities 2020	Locked cities 2020	Normal cities 2020
Control group	Locked cities 2019	Unlocked cities 2020	Normal cities 2019
	(1)	(2)	(3)
Treat * Post	− 0.127***	− 0.083***	–
	(0.023)	(0.020)	–
Treat * PostWuhan	− 0.054**	− 0.038*	− 0.114***
	(0.023)	(0.020)	(0.010)
Weather	Yes	Yes	Yes
Fixed effects	Yes	Yes	Yes
Constant	3.880***	3.846***	3.906***
	(0.036)	(0.024)	(0.018)
Observations	6602	13,858	20,996
R2	0.528	0.580	0.576

This table reports the spillover effect of the lockdown policy. Column (1) compares the locked cities in 2020 to itself in 2019, column (2) compares the locked cities in 2020 to unlocked cities in 2020, and column (3) compares the unlocked cities in 2020 to itself in 2019. All columns present the regression with both the weather conditions and fixed effects. The dependent variable is $\mathit{AQI}$. The key independent variable is $Treat\ast PostWuhan$. Significance at 10%, 5%, and 1% levels was indicated by *, **, and ***, respectively