人口结构是否会影响国际贸易?一方面,高劳动人口比例会使出口国产出增加,从而增加出口;另一方面,高劳动人口比例也会给进口国带来更多的劳动收入,从而增加进口。本文利用176个国家从1970年到2006年的大样本面板数据,并控制多边阻力等因素,在引入劳动人口比之后,对贸易引力方程的回归分析支持了如下理论预测:贸易国的劳动人口比例上升会增加双边贸易流;出口国(进口国)平均劳动人口比上升1%,出口(进口)会上升至少3%(2%)。这一发现对于理解人口大国(如中印)或贸易大国(如中美)的贸易具有重要的理论和现实意义。

This paper explores whether educational attainment has a cognitive reserve capacity in elder life. Using pilot data from the China Health and Retirement Longitudinal Study (CHARLS), we examined the impact of education on cognitive abilities at old ages. OLS results showed that respondents who completed primary school obtained 18.2 percent higher scores on cognitive tests than those who did not. We then constructed an instrumental variable (IV) by leveraging China's Great Famine of 1959–1961 as a natural experiment to estimate the causal effect of education on cognition. Two-stage least squares (2SLS) results provided sound evidence that completing primary school significantly increases cognition scores, especially in episode memory, by almost 20 percent on average. Moreover, Regression Discontinuity (RD) analysis provides further evidence for the causal interpretation, and shows that the effects are different for the different measures of cognition we explored. Our results also show that the Great Famine can result in long-term health consequences through the pathway of losing educational opportunities other than through the pathway of nutrition deprivation.