Table 6.

Balancing test for propensity score matching

	Mean		t test
Variables	Treated	Matched	t statistic	p value
Temperature	16.876	17.048	−0.17	0.867
precipitation	81.813	87.731	−0.49	0.629
Log export	11.670	12.152	−0.57	0.571
Log population	8.286	8.508	−0.88	0.381
Log GDP per capita	9.224	9.261	−0.23	0.817
Industry value‐added share	0.422	0.407	0.48	0.635
Log distance from a port	5.825	5.528	0.76	0.449

Note: The nearest neighbor matching approach is used to match the treated cities with four control cities, and the t test results indicate that there are no significant differences in covariate means after the matching.