Table 1.
The descriptive statistics of the main variables.
| Variable name | Indicators | Observation number (Obs.) | Mean | Standard deviation | Min | Max |
|---|---|---|---|---|---|---|
| PM2.5 | PM2.5 | 2625 | 3.5556 | 0.4661 | 1.0508 | 4.5357 |
| GDP share of the secondary sector | InduStru | 2625 | 3.8556 | 0.2218 | 2.6283 | 4.4502 |
| GDP per capita | Econ | 2625 | 7.6401 | 1.9219 | 4.1891 | 14.5811 |
| the proportion of local scientific enterprise expenditure in fiscal expenditure | Sci | 2625 | −4.6615 | 0.8634 | −8.2141 | −1.5758 |
| the proportion of local education expenditure in fiscal expenditure | Edu | 2625 | −1.7056 | 0.2584 | −4.2581 | −0.9744 |
| the number of new contracts signed by foreign investors | Invest | 2625 | 4.9100 | 0.5058 | 0.9549 | 7.9950 |
| temperature | Temp | 2625 | 3.1995 | 0.6321 | 1.9751 | 7.9352 |
| wind | Wind | 2625 | 4.2613 | 0.2025 | 3.5906 | 6.4336 |
| relative humidity | Hum | 2625 | 3.0991 | 1.6272 | 0.0000 | 8.5362 |