Governments worldwide have taken unprecedented social distancing and community lockdown measures to halt the COVID-19 epidemic, leaving millions of people restrained in locked-down communities and their mental well-being at risk. This study examines Chinese rural residents' mental health risk under emergency lockdown during the COVID-19 pandemic. It investigates how the environmental, socioeconomic, and behavioral dimensions of community support affect mental health in this emergency context. We also explore whether community support's effectiveness depends on the strictness of lockdown measures implemented and the level of individual perceived COVID-19 infection risk. We collect self-reported mental health risk, community support, and demographics information through a cross-sectional survey of 3892 Chinese rural residents living in small towns and villages. Ordinary least square regressions are employed to estimate the psychological effects of community support. The results suggest that the COVID-19 epidemic and lockdown policies negatively affect psychological well-being, especially for rural females. The capacity for community production has the largest impact on reducing mental health risks, followed by the stability of basic medical services, community cohesion, housing condition, the stability of communications and transportation supply, and the eco-environment. The effectiveness of different community support dimensions depends on the level of lockdown policy implemented and the levels of one's perceived risk of COVID-19 infection. Our study stresses the psychological significance of a healthy living environment, resilient infrastructure and public service system, and community production capacity during the lockdown in rural towns and villages.

This study revisits the association between bilateral relations and trade based on rare-event data from Integrated Data for Event Analysis (IDEA). Our results suggest that a country imports more from another if the two countries are friendlier. We further argue that states face two constraints when attempting to manipulate trade. First, they are constrained by domestic institutions such as elections and Congress. Second, they are constrained by international institutions such as the World Trade Organization (WTO). Our results show that the imports of authoritarian countries follow the flag of politics, but democratic countries' imports are less likely to be affected by bilateral relations. Moreover, WTO membership can gradually restrict democratic states from intervening on imports but has little impact on authoritarian governments.

This research sheds light on the link between social norms and economic development. It explores the determinants of inheriting the mother’s surname in China and its implications for children’s health status and education outcomes. It establishes that children whose mothers are younger, more educated, and from regions with a lower sex ratio are more likely to be named after their mother. Moreover, these children have superior health and education outcomes, reflecting predominantly the impact of women’s higher bargaining power on children’s human capital accumulation.

Background Some bereaved parents experience a decreasing trajectory of grief, while others fail to adapt over the long term and persistently suffer from negative health consequences. This study investigates the mediating role of social integration in the relationship between losing an only child and parental health in a family-oriented society. Method A sample of 1828 bereaved parents and 4739 non-bereaved parents was drawn from a 10-city survey in China. Regression methods were used to examine the impact of child loss on parental health, and Sobel test was applied to examine the mediating role of social integration. Results Bereaved parents who lost their only child have worse self-rated health and more negative affect than the non-bereaved parents, which lasted for years after the death of the only child. The Sobel test shows that 24.8% of the total effects on self-rated health and 6.7% of the total effects on negative affect can be explained via decreased social integration. The gender of parents and child as well as fertility intentions are important sources of heterogeneity in the Chinese culture. Limitation The results based on cross-sectional data may only reveal correlation rather than causality. The data was retrieved from self-reported questionnaires and there is a lack of objective measures of parental health. Moreover, the detailed mechanisms behind how child loss resulted in less social integration should be further explored. Conclusions Significant disparities in health outcomes and social integration were found for bereaved parents relative to the non-bereaved parents. Future work is needed to assess the health of bereaved parents, identify the vulnerable and disadvantaged groups, and design inclusive intervention programs.

家户层面的股票投资不仅是家庭进行资产配置的重要渠道，也是国家金融市场建设的重要环节。本文利用中国义务教育法的实施作为自然实验，基于2015年中国家庭金融调查（CHFS）的数据研究了受教育水平对家户股票市场参与的因果效应。本文发现，教育能显著地提高家庭参与股票市场的概率；但是，没有证据表明高教育水平的家户可以获得更高的股票收益。更进一步地分析发现，教育会通过提升金融知识和改变风险态度等渠道，影响家庭的股票市场参与行为。本文的实证结果表明，提升国民的总体教育水平，不仅可以帮助家庭通过金融市场渠道，优化财富配置，还有助于我国的金融市场良性、健康发展。

This paper employs industrial robot installations that represent the level of smart manufacturing as the proxy variable of artificial intelligence(AI). Based on crosscountry panel data and China’s provincial panel data, we create a two-stage least square(2 SLS) regression model to examine the effect of an aging population on AI applications and AI’s effect on economic growth. In this manner, we aim to test whether AI has a substitutive effect on labor against the backdrop of an aging society and the kind of such a substitutive effect. Our findings suggest that the labor shortage arising from an aging society will prompt an economy to adopt smart manufacturing more broadly, i.e. an aging society is a driver of AI development. Smart manufacturing has a positive effect on local GDP and helps shore up the slowing economy resulting from an aging society. AI is an important tool for coping with the challenges of an aging society. Current AI development is an "induced innovation," and its substitutive relationship with labor is a "supplemental substitution" rather than "crowding-out substitution." If these characteristics are properly maintained, AI will contribute more to China’s economy against the backdrop of an aging society. 

本文将人口结构变迁所导致的消费需求变化、行业的盈利与行业股票的回报联系起来研究。具体来说,不同商品的消费者年龄结构会有不同。基于对未来人口结构的预测,能预测各个行业因人口结构变化所致的需求变化,进而预测行业的盈利状况。基于中国A股市场数据的实证结果表明,人口结构变迁信息的需求变化估计能很好地预测行业盈利水平,但无法很好地预测股票的未来回报。另外,本文没有发现基于人口结构变化构建的多空投资组合能获得超额回报。企业可以将人口信息用于决策来获得盈利,但是投机者却无法做到。 

劳动力的空间自由流动是一个国家长期经济增长的重要推动力。对中国而言，自1978年以来，近40年经济持续高速增长背后的机制是成万上亿的农村劳动力流向城市部门的宏大变迁。随着中国劳动力增量的逐步下降甚至为负，如何盘活农村剩余劳动力促进城乡之间劳动力的流动是我国目前面临的重要挑战。文章基于中国居民收入调查数据库（CHIPS2002和CHIPS2013），从教育的外部性视角系统分析了农村地区教育程度的提高是否会促进当地农民外出就业。研究发现，平均教育程度的增加对外出就业存在两种相反的作用力。首先，农村地区平均教育程度的提高会促进当地企业的发展，进而抑制当地农民外出；另一方面，当地平均教育程度的提高会增强农民工社会网络对农民工外出就业的促进作用，进而促进当地农民外出就业。因此，农村地区平均教育程度对外出就业的影响取决于当地企业的发展水平以及当地的农民工社会网络的强弱。文章最后使用工具变量法等稳健性检验的结果也支持了上述研究发现。文章的政策含义是：农村地区的发展政策可能也要因地制宜。对当地企业发达或有潜力发展乡镇企业的地区，可能提高农村教育和相关技能培训，鼓励农民回乡创业更好；而对其他地区，可以完善农村社会网络，增强乡民联系，以更好地促进农民外出。

文章基于跨国面板数据和中国省级面板数据,构建二阶段最小二乘回归模型,通过研究人口老龄化如何影响人工智能应用及人工智能应用如何影响经济增长,考察在老龄化背景下,人工智能对劳动力是否存在替代效应和存在怎样的替代效应。研究结果表明,人口老龄化导致的劳动力短缺会促使一个经济体更多地应用智能化生产,人口老龄化是人工智能发展的诱因;智能化生产对当地生产总值有正向影响,有助于抵偿人口老龄化所造成的经济增长放缓,人工智能是应对老龄化的重要工具。当前人工智能发展属于"诱导式创新",与劳动力之间是替代关系,而且是"补位式替代",不是"挤出式替代"。如果维护好这些特征,人工智能将在未来老龄化大背景下为中国经济做出更大的贡献。

Background Due to the sustained increases in life expectancy over the past half century, the elderly today will receive supports from their children for a longer period than ever before. Therefore, understanding the spillover effects of children's socioeconomic status on parents' health becomes increasingly important for both scholars and policy makers. Methods The Ordinary Least Squares regression is applied to the China Health and Retirement Longitudinal Study 2011, a national representative dataset including approximately 10 000 households and 17 600 middle-aged and elderly respondents. The Sobel test is used to examine the mediation role of social integration. Results The elderly who have a cadre child reported better health (coefficient=0.1347; 95% CI 0.067 to 0.202), had fewer activities of daily living (ADLs) limitations (coefficient=−0.1289; 95% CI −0.216 to −0.042) and were more socially integrated (coefficient=0.2321; 95% CI 0.103 to 0.361). Such effects are mainly driven by the parents of higher-ranking cadres. For the parents of higher ranking cadres, the Sobel test suggests that 12.6% of the total effects on self-reported health and 21.9% of the total effects on ADL limitations are mediated by the increase in parents' social integration. Conclusion The findings suggest positive spillover effects of children's political status on parents' health. The benefits of having a cadre child are at least equivalent to the rural–urban gap in health and even stronger for the parents of higher ranking cadres. One potential explanation for such spillover effects is that a child's political status can improve parents' community involvement and social interactions.

本文使用中国居民收入调查数据库2008年农村住户调查（CHIP2008）数据,将最早外出时间在1984年到1992年之间的农民工定义为早期农民工,基于我国城乡劳动力市场的信息不完全,我们分析了他们在城乡劳动力转移中的先驱效应。实证结果表明,早期农民工越多的地区,当地的农民外出的概率也越高,即城乡劳动力转移中存在先驱效应。考虑到信息传播的质量,我们根据早期农民工的平均教育以及当地其他农民的平均教育进行分组回归,发现教育程度较高的地区,先驱效应越强。本文还发现,先驱越多的地区,当地外出的农民工的行业集聚特征越明显。作为稳健性检验,早期农民工定义的调整以及将1978年以前因外生因素外出的农村劳动力作为早期农民工的替代变量的分析都没有改变文章的结果。

Why are contemporary populations still aging? In the classic view, population aging has been driven almost entirely by fertility decline over the demographic transition, while mortality decline has played a minor role. In this view, populations today are still aging because they are still converging toward the new older stable age distribution. But in the past 25 years an elegant mathematical decomposition of changing mean ages has sometimes been interpreted as showing that recent aging is mainly due to declining mortality rather than fertility. Here we question this interpretation and argue that it is necessary to evaluate the indirect effects of mortality change as well as the direct ones. We suggest that the gold standard for this problem is the analytic simulation with explicit counterfactual comparisons. Analytic simulations show that fertility decline is largely responsible for the old age of contemporary populations and has by far the largest role in accounting for continuing aging from 2005–2010.

This paper investigates whether children’s political success contributes to social stratification and health inequality among older adults. Using China Health and Retirement Longitudinal Study (CHARLS) data, we investigate whether having a cadre (i.e., politically employed) child substantially increases overall cognitive functioning among older adults. We find that the beneficial effect of having a cadre child on cognitive functioning is equivalent to a 1.5-year increase in education, even after controlling for other variables related to general intelligence. This positive effect is more salient among parents of higher-ranking cadre children, and more salient in less-marketized regions. The results of a Sobel test suggest that about one-fifth of the effect can be explained by the channel of increased social interaction.

We endogenize credit misallocation by introducing the government’s preference. The local government determines the credit subsidy to SOEs after a trade-off between SOEs’ profits and local aggregate outputs. Credit misallocation is more severe in regions where SOE share is high.

We develop a model of firms' auditor choices when presented with a heterogeneous group of investors. We show that firms' auditor choices in equilibrium depend on the composition of investors in the market. The signaling effect of choosing a high-quality auditor exists only when there is at least a certain proportion of sophisticated investors. If there is a sufficiently high proportion of sophisticated investors, then all firms will choose high-quality auditors. We also show that the overall audit quality in the market increases with an increasing proportion of sophisticated investors. When the audit market is differentiated and investors are heterogeneous, an increase in the penalty for firms that receive a qualified opinion will lead to a decrease in the overall audit quality in the market. Our conclusions remain valid even after taking audit fees, auditor quality change, and firm heterogeneity into consideration.

本文利用长期面板数据,对玉米被引入中国后,对明清农民起义发生率的影响进行了定量分析。分析结果显示,玉米播种时间和农民起义发生率存在U形关系:短期内,玉米的引种确实有助于降低气候灾害引发的农民起义的发生率,但这种效应是逐渐减弱的。到清朝中后期,玉米播种时间更久的地区甚至更易受水旱灾害危害,进而更易爆发农民起义。这说明了以玉米为代表的美洲作物的引种并未能让中国像欧洲国家那样摆脱"气候—治乱循环"。 

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.