Booming with Speed: High-Speed Rail and Regional Green Innovation

Table 5

Heterogeneity analysis on economic zones and urban agglomerations.

	Panel A: four economic zones				Panel B: four urban agglomerations
	East	Center	West	Northeast	BTH	YRD	CY	PRD
	GUMA				GUMA
	(1)	(2)	(3)	(4)	(1)	(2)	(3)	(4)
L.HSR	0.240	0.0138	0.170	0.0491	0.0387	0.162	0.392	0.108
	(0.0558)	(0.0146)	(0.0646)	(0.0398)	(0.0954)	(0.0680)	(0.140)	(0.227)
R^2	0.520	0.353	0.224	0.306	0.796	0.653	0.563	0.824
Test of group: coefficient difference	East vs. west				YRD vs. CY
Observed difference	0.198				−0.230
	GIA				GIA
	(5)	(6)	(7)	(8)	(5)	(6)	(7)	(8)
L.HSR	0.252	0.00420	0.255	0.0924	-0.0632	0.222	0.463	0.175
	(0.0674)	(0.0298)	(0.0788)	(0.0753)	(0.128)	(0.0891)	(0.149)	(0.294)
R^2	0.407	0.289	0.217	0.240	0.728	0.566	0.541	0.782
Test of group: coefficient difference	East vs. west				YRD vs. CY
Observed difference	−0.008				−0.241
	GUMG				GUMG
	(9)	(10)	(11)	(12)	(9)	(10)	(11)	(12)
L.HSR	0.224	0.0183	0.146	0.0484	0.0214	0.168	0.352	0.120
	(0.0506)	(0.0131)	(0.0582)	(0.0366)	(0.0971)	(0.0610)	(0.122)	(0.182)
R^2	0.502	0.356	0.210	0.298	0.788	0.640	0.562	0.823
Test of group: coefficient difference	East vs. west				YRD vs. CY
Observed difference	0.074				-0.184
	GIG				GIG
	(13)	(14)	(15)	(16)	(13)	(14)	(15)	(16)
L.HSR	0.0663	0.00740	0.0536	0.0289	0.00520	0.0518	0.101	0.0941
	(0.0161)	(0.00589)	(0.0190)	(0.0208)	(0.0176)	(0.0196)	(0.0325)	(0.0608)
R^2	0.390	0.259	0.184	0.263	0.731	0.533	0.527	0.780
Test of group: coefficient difference	East vs. west				YRD vs. CY
Observed difference	0.010				−0.049
Controls	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Year	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
City	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
N	1177	1120	1150	476	224	640	256	144

Note: in Panel A, cities in our estimation sample are divided into four groups based on the location of these cities (i.e., the east, the center, the west, and the northeast economic zones). In Panel B, cities in four urban agglomerations are selected as samples to test the heterogeneity of HSR’s effect on regional green innovation (i.e., the BTH, the YRD, the CY, and the PRD). The test of coefficient difference between groups is carried out using the bootstrap method. The bootstrap number in this paper is set to bs (1000). HSR and all control variables are included and lagged by one year in all regressions. All regressions include city fixed effects and year fixed effects. Robust standard errors in parentheses are clustered at the city level. The symbols , and indicate significance at the 1%, 5%, and 10% levels, respectively.