fig9

Figure 9. Two-stage least squares (2SLS) results using instrumental variables. Upper panels compare OLS and 2SLS point estimates; error bars represent approximate 95% confidence intervals (point estimate ± 1.96 HC3-robust SE) for both estimators. Lower panels show alternative-instrument 2SLS point estimates without confidence intervals. Each regression uses N = 390 province-year observations from 30 provinces over 2012-2024. OLS intervals here use HC3 standard errors; Table 3 uses Newey-West HAC standard errors. ***P < 0.01, **P < 0.05, *P < 0.10. 2SLS: Two-stage least squares; OLS: ordinary least squares; IV: instrumental variable.