Modeling the Impact of Innovation on Economic Quality and Environmental Pollution Change under Consideration of Environmental Regulation

Table 2

Variable definition.

Variable classification	Variable name	Variable interpretation	Symbol	References
Explained variable	Green total factor productivity	Malmquist–Luenberger index based on nonradial SBM directional distance	GTFP	[38, 39]
	Total factor productivity	DEA-Malmquist index	TFP	[28]
	Emissions	Industrial wastewater discharge (IWD), industrial sulfur dioxide discharge (SO2), industrial smoke and dust discharge (ISD)	CON	[40–44]
Explanatory variables	Number of patents (ten thousand)	Number of patents = number of invention patents + number of utility patents + number of appearance patents	INV	[45, 46]
Threshold variable	Environmental regulation	Entropy weight method based on five indicators: industrial SO2 removal rate, smoke removal rate, the comprehensive utilization rate of industrial solid waste, domestic sewage treatment rate, and domestic garbage innocuous treatment rate	REGU	[47, 48]
Control variable	Industrial structure	The ratio of the added value of the tertiary industry to the added value of the secondary industry	IS	[49, 50]
	Open to the outside world	The proportion of the output value of foreign-invested enterprises in the regional GDP	FDI	[51, 52]
	Government action	Government expenditure on teaching and research as a percentage of the regional GDP	GOV	[53]
	Infrastructure	Urban road area per capita	ROD	[54]