The effects of smart city construction on urban green total factor productivity: evidence from China

Figures & data

Table 1. Variable descriptive statistics.

Variable	Obs	Mean	Standard	Min	Max
lngtfp	3,728	0.799	0.178	0.0569	1.527
lneffch	3,728	0.702	0.0793	0.422	1.087
lntech	3,728	0.792	0.174	0.0681	1.655
scc	3,728	0.175	0.380	0	1
lnagg	3,728	1.247	0.667	0.171	3.780
lnsgdp	3,728	3.734	0.288	2.149	4.378
lnpopden	3,728	6.376	0.985	2.523	9.551
lnte	3,728	0.170	0.163	0.00031	1.797
lninf	3,728	6.170	0.994	2.079	9.892
lnedu	3,728	1.206	0.352	0.0141	2.876
lninvest	3,728	4.174	0.437	2.274	5.504
lnfdi	3,728	6.506	1.861	0.153	11.35
lngov	3,728	2.728	0.472	0.704	4.968

Source: Author’s estimation.

Table 2. Mutually beneficial effect of smart city construction.

Variables	(1)	(2)	(3)	(4)	(5)	(6)
	lnGDP	lnPGDP	lnSO2	lnwaste	lnsmoke	polluindex
scc	0.032***	0.024***	−0.095***	−0.165***	−0.089**	−0.284***
	(4.02)	(2.92)	(−2.71)	(−5.70)	(−2.09)	(−3.43)
Control	YES	YES	YES	YES	YES	YES
City FE	YES	YES	YES	YES	YES	YES
Year FE	YES	YES	YES	YES	YES	YES
Constants	13.929***	8.365***	9.953***	11.829***	11.131***	0.080
	(125.20)	(73.44)	(20.32)	(30.88)	(18.70)	(0.07)
N	3728	3728	3728	3728	3728	3728
R-squared	0.960	0.954	0.565	0.161	0.249	0.154

Notes: ***, **, * is significant at the 1%, 5%, and 10% levels respectively; data in parentheses are t-statistics.

Source: Author’s estimation.

Table 3. Direct impact of smart city construction on GTFP.

Variables	(1)	(2)	(3)	(4)	(5)
	lngtfp	lngtfp	lngtfp	lneffch	lntech
scc	0.020***	0.037***	0.034***	−0.0005	0.034***
	(3.53)	(5.86)	(5.45)	(−0.14)	(5.93)
Control	YES	NO	YES	YES	YES
City FE	YES	YES	YES	YES	YES
Year FE	YES	YES	YES	YES	YES
Constants	1.280***	0.716***	1.235***	0.787***	1.159***
	(16.18)	(115.01)	(14.20)	(16.35)	(14.57)
N	4544	3728	3728	3728	3728
R-squared	0.411	0.326	0.364	0.078	0.419

Note: ***, **, * is significant at the 1%, 5%, and 10% levels respectively; data in parentheses are t-statistics.

Source: Author’s estimation.

Figure 1. common trend test.

Source: Author’s estimation.

Table 4. Results of the survival analysis.

Variables	(1)	(2)
	lnT	lnT
lngtfp	−0.045	−0.0003
	(−1.01)	(−0.01)
Control	NO	YES
Constants	2.753***	2.818***
	(60.31)	(51.06)
N	1083	1083

Note: ***, **, * is significant at the 1%, 5%, and 10% levels respectively; data in parentheses are t-statistics.

Source: Author’s estimation.

Table 5. Results of PSM-DID.

Variables	Kernel matching	Nearest neighbor matching	Radius matching
scc	0.027***	0.029***	0.028***
	(4.45)	(4.68)	(4.58)
Control	YES	YES	YES
City FE	YES	YES	YES
Year FE	YES	YES	YES
Constants	1.295***	1.262***	1.296***
	(14.69)	(14.43)	(14.69)
N	3683	3692	3687
R-squared	0.381	0.375	0.380

Note: ***, **, * is significant at the 1%, 5%, and 10% levels respectively; data in parentheses are t-statistics.

Source: Author’s estimation.

Table 6. Results of excluding other policies.

Variables	(1)	(2)	(3)	(4)	(5)
	Excluding innovative pilot cities	Excluding emission trading pilot cities	Excluding new energy pilot cities	Excluding environmental protection model pilot cities	Excluding all pilot cities
scc	0.034***	0.042***	0.038***	0.023***	0.037***
	(5.08)	(5.28)	(5.94)	(3.32)	(3.97)
Control	YES	YES	YES	YES	YES
City FE	YES	YES	YES	YES	YES
Year FE	YES	YES	YES	YES	YES
Constants	1.183***	1.437***	1.338***	1.268***	1.469***
	(13.32)	(13.97)	(15.24)	(13.57)	(13.07)
N	3518	2916	3485	3303	2387
R-squared	0.336	0.305	0.345	0.321	0.235

Note: ***, **, * is significant at the 1%, 5%, and 10% levels respectively; data in parentheses are t-statistics.

Source: Author’s estimation.

Table 7. Results of other tests.

Variables	(1) Change the explained variables	(2) Refine pilot time
scc	0.024***
	(6.87)
scc’		0.034***
		(5.49)
Control	YES	YES
City FE	YES	YES
Year FE	YES	YES
Constants	0.175***	1.236***
	(3.78)	(14.21)
N	3728	3728
R-squared	0.331	0.316

Note: ***, **, * is significant at the 1%, 5%, and 10% levels, respectively; data in parentheses are t-statistics.

Source: Author’s estimation.

Table 8. Mechanism analysis of smart city construction on GTFP.

Variables	(1)	(2)	(3)
	number of patents granted per capita	industrial structure upgrading	ratio of capital-to-labour
scc	0.424***	0.037**	0.209***
	(14.89)	(2.46)	(11.13)
Control	YES	YES	YES
City FE	YES	YES	YES
Year FE	YES	YES	YES
Constants	−8.387***	−5.148***	6.812***
	(−22.24)	(−25.96)	(27.32)
N	3728	3728	3728
R-squared	0.664	0.543	0.586

Note: ***, **, * is significant at the 1%, 5%, and 10% levels respectively; data in parentheses are t-statistics.

Source: Author’s estimation.

Figure 2. Placebo test.

Source: Author’s estimation.

Table 9. Heterogeneity results of the impact of smart city construction on GTFP.

Variables	(1)	(2)	(3)	(4)
	City scale	City rank	City region	City location
scc	0.029***	0.028***	0.015**	0.052***
	(4.24)	(4.37)	(2.16)	(7.91)
scc × scale	0.072***
	(6.68)
scc × rank		0.055***
		(3.61)
scc × region			0.080***
			(7.06)
scc × huline				−0.109***
				(−8.26)
Control	YES	YES	YES	YES
City FE	YES	YES	YES	YES
Year FE	YES	YES	YES	YES
Constants	0.371***	1.233***	1.237***	1.200***
	(4.73)	(14.19)	(14.32)	(13.91)
N	3728	3728	3728	3728
R-squared	0.269	0.366	0.373	0.376

Note: ***, **, * is significant at the 1%, 5%, and 10% levels, respectively; data in parentheses are t-statistics.

Source: Author’s estimation.