Table 1 Variable definition and descriptive statistics.
Variable | Definition | Obs | Mean | Std. dev. | Min | Max | VIF |
|---|---|---|---|---|---|---|---|
Explained variables | |||||||
 lnpgdp | Natural logarithm of GDP per capita (yuan) | 37,373 | 9.849 | 1.008 | 4.280 | 19.870 | – |
 eq | Ecological Index | 37,373 | 0.545 | 0.141 | 0.020 | 0.890 | – |
Core explanatory variable | |||||||
 policy | NRP for ORBAs | 37,373 | 0.063 | 0.243 | 0 | 1.000 | 1.06 |
Control variables | |||||||
 agri | Value-added of primary industry (100 million yuan) | 37,373 | 20.108 | 19.204 | 0.083 | 173.409 | 1.58 |
 den | Year-end population /acreage (people/km2) | 37,373 | 298.888 | 288.524 | 0.110 | 2,895.410 | 1.35 |
 fiscal | Fiscal expenditure (100 million yuan) | 37,373 | 22.317 | 25.847 | 0.179 | 413.640 | 1.51 |
 tem | Average annual temperature (℃) | 37,373 | 13.571 | 5.413 | -4.130 | 26.400 | 2.22 |
 pre | Average annual precipitation (mm) | 37,373 | 936.071 | 527.662 | 30.420 | 3,939.890 | 2.28 |
 sun | Sunshine hours (h) | 37,373 | 2,060.047 | 554.969 | 602.82 | 4,327.340 | 1.93 |
