Table 1. Statistical description†.
| 2016 | 2014 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Variable | Obs | Mean | Std. Dev. | Min | Max | Obs | Mean | Std. Dev. | Min | Max |
| Depression | 13761 | 0 | 1 | -0.989 | 4.997 | 18229 | 0 | 1 | -0.761 | 5.509 |
| Cognitive ability | 13761 | 0 | 1 | -2.487 | 3.004 | 18229 | 0 | 1 | -1.687 | 2.174 |
| Non-cognitive ability | 13761 | 0 | 1 | -2.832 | 1.331 | 18229 | 0 | 1 | -2.897 | 1.408 |
| PM2.5 | 13761 | 38.625 | 16.775 | 2.642 | 80.97 | 18229 | 40.470 | 15.068 | 2.952 | 77.68 |
| Relative Income | 13761 | 2.411 | 1.009 | 1 | 5 | 18229 | 2.496 | 0.974 | 1 | 5 |
| Social Status | 13761 | 2.825 | 1.058 | 1 | 5 | 18229 | 2.893 | 0.981 | 1 | 5 |
| Age | 13761 | 49.879 | 15.183 | 18 | 98 | 18229 | 46.627 | 15.504 | 16 | 95 |
| Gender | 13761 | 0.494 | 0.500 | 0 | 1 | 18229 | 0.515 | 0.500 | 0 | 1 |
| Male | 6801 | (49.42%) | 9380 | (51.46%) | ||||||
| Female | 6960 | (50.58%) | 8849 | (48.54%) | ||||||
| Urban | 13761 | 0.481 | 0.500 | 0 | 1 | 18229 | 0.505 | 0.500 | 0 | 1 |
| Urban | 6672 | (48.48%) | 9361 | (51.35%) | ||||||
| Rural | 7089 | (51.52%) | 8868 | (48.65%) | ||||||
| Marital | 13761 | 2.111 | 0.775 | 1 | 5 | 18229 | 2.090 | 0.776 | 1 | 5 |
| Never married | 1111 | (8.07%) | 1755 | (9.63%) | ||||||
| Married | 11646 | (84.63%) | 15168 | (83.21%) | ||||||
| Cohabitation | 77 | (0.56%) | 101 | (0.55%) | ||||||
| Divorced | 219 | (1.59%) | 315 | (1.73%) | ||||||
| Widowed | 708 | (5.14%) | 890 | (4.88%) | ||||||
| Education Degree | 13761 | 2.564 | 1.329 | 1 | 7 | 18229 | 2.706 | 1.334 | 1 | 8 |
| Illiterate | 3779 | (27.46%) | 4107 | (22.53%) | ||||||
| Primary school | 3040 | (22.09%) | 4143 | (22.73%) | ||||||
| Junior high school | 3927 | (28.54%) | 5443 | (29.86%) | ||||||
| Senior high school | 1881 | (13.67%) | 2798 | (15.35%) | ||||||
| 3-year college | 704 | (5.12%) | 1059 | (5.81%) | ||||||
| Bachelor's degree | 404 | (2.94%) | 639 | (3.51%) | ||||||
| Master's degree | 26 | (0.19%) | 39 | (0.21%) | ||||||
| Doctoral degree | 0 | (0%) | 1 | (0.01%) | ||||||
†Notes: Depression is measured by the Center for Epidemiological Studies Depression Scale (CES-D) in 2016 and Kessler Screening Scale for Psychological Distress (K6) in 2014. Percentages of each category of categorical variables are in the parentheses.