The Impact of Green R&D Activities on SO₂ Emissions: Evidence from China

Table 1

Definition and data description of the variables.

Code	Definition	Proxy variables
PSO	SO2 emissions per capita	The ratio of the SO2 emissions divided by population
PGDP	GDP per capita	The rate of GDP divided by the population gross
IND	Economic structure	The rate of the added value in the secondary industries in GDP
ENSTR	Energy structure	The rate of coal consumption in total energy
UR	Urbanization	The ratio of urban population to the population gross
GRD	Green R&D operations	The figure of green patents
UGRD	Utility green R&D operations	The figure of utility green patents
CGRD	Creation green R&D activities	The figure of creation green patents
FEP	Full-time equivalent of R&D personnel	The figure of R&D staff recruited regarding their working hours