Table 7.

Size heterogeneity.

Variable	(1)	(2)	(3)	(4)
	Super	Large	Medium	Small
AQI	−7.478**	−4.530**	−5.384***	−0.244
	(2.805)	(1.852)	(1.819)	(0.697)
College	−1.973	0.377	0.179	1.015
	(3.006)	(3.638)	(1.376)	(1.430)
Teacher	2.914	1.969	1.774*	0.245
	(5.384)	(1.691)	(1.011)	(0.891)
FDI	−0.394	−0.293	−0.500**	−0.164
	(0.483)	(0.240)	(0.210)	(0.161)
gov	1.503*	1.599**	0.748**	0.758*
	(0.774)	(0.655)	(0.353)	(0.386)
Industry	−11.630***	−9.441***	−7.514***	−5.634***
	(1.085)	(1.236)	(1.743)	(1.396)
gdp	20.760***	20.050***	25.040***	18.630***
	(1.993)	(2.238)	(1.653)	(1.101)
Constant	−90.690*	−96.730***	−123.200***	−101.200***
	(51.020)	(21.030)	(17.920)	(12.930)
City and year	Control	Control	Control	Control
R-squared	0.690	0.620	0.612	0.634
Number of cities	30	46	109	69

Robust standard errors in parentheses,

^***p < 0.01,

^**p < 0.05,

^*p < 0.1.