At the intersection of physical sciences and policy, our researchers work to find solutions for hunger, environmental degradation, emerging energy markets and more.
Research Spotlight
Economic Policy Challenges Facing California's Next Governor: Electricity Policy Reform
Because Californians are likely to want to continue to lead the energy transition, the relevant policy design question is: How can the state achieve these low-carbon energy goals in a more cost- effective manner?
Climate Change is Increasing the Risk of Extreme Autumn Wildfire Conditions Across California
The climate model analyses presented here suggest that continued climate change will further amplify the number of days with extreme fire weather by the end of this century, though a pathway consistent with the UN Paris commitments would substantially curb that increase.
Sight for Sorghums: Comparisons of Satellite- and Ground-Based Sorghum Yield Estimates in Mali
Leveraging a survey experiment in Mali, this study uses plot-level sorghum yield estimates, based on farmer reporting and crop cutting, to construct and evaluate estimates from three satellite-based sensors.
National Bureau of Economic Research,
June 14, 2022
A new method to test for efficient risk pooling allows for intertemporal smoothing, non-homothetic consumption, and heterogeneous risk and time preferences.
Annual Review of Resource Economics,
June 13, 2022
One out of every three children under age 5 in developing countries lives in conditions that impede human capital development. In this study, we survey the literature on parenting training programs implemented before age 5, with the aim to increase parental investment in human capital accumulation in developing countries. Our review focuses on the implementation and effectiveness of parenting training programs (i.e., training in child psychosocial stimulation and/or training about nutrition). We emphasize the mechanisms that drive treatment-induced change in human capital outcomes and identify the demand- and supply-side behaviors that affect efficacy and effectiveness. Although the literature includes evidence on program features that are associated with successful interventions, further evidence on the dynamics of human capital formation, documentation of medium- to long-term persistence of treatment impacts, and research on the implementation and evaluation of programs at scale are needed to delineate a scalable and inclusive program that provides long-term treatment impacts.
International Journal of Environmental Research and Public Health,
June 13, 2022
This paper examines the impact of parental beliefs on child development outcomes (for both cognitive and social–emotional skills) based on a three-wave longitudinal survey in rural China. The survey waves were conducted when the sample children were 18–30 months, 22–36 months, and 49–65 months, respectively. A total of 815 children and their primary caregivers who participated in all three wave surveys were enrolled in this study. Using difference-in-differences and propensity score matching approaches, the results indicate that strengthened parental beliefs have a positive and significant impact on child social–emotional development. Specifically, between the periods of the Wave 1 survey (when children were 18–30 months old) and the Wave 3 survey (when children were 49–65 months old), and between the Wave 2 survey (when children were 22–36 months old) and the Wave 3 survey, strengthened parental beliefs were causally associated with more favorable child social–emotional scores by 0.44 SD (p < 0.01) and 0.49 SD (p < 0.01), respectively. No significant impact, however, was found between the period of the Wave 1 survey and the Wave 2 survey. In contrast, weakened parental beliefs had a negative and significant impact on child social–emotional development. Specifically, weakened parental beliefs were causally associated with worse child social–emotional abilities by 0.35 SD (p < 0.01), 0.30 SD (p < 0.01), and 0.22 (p < 0.05) for the time period of the Wave 1 to Wave 2, Wave 1 to Wave 3, and Wave 2 to Wave 3, respectively. No significant impact of parental beliefs, however, was found on child cognitive development. In addition, the findings of the mediation analysis show that only a marginal impact of parental beliefs on child social–emotional development can be indirectly explained by parental beliefs through parenting practices. This study calls on policy makers to improve parental beliefs and parenting practices in the hope that it will lead to better child development in rural China.
China’s college admission increased by five times between 1998 and 2009. While the college premium for young workers declined, that for senior workers increased in this period. In our general equilibrium model, a rising demand for skills (education and experience) explains both trends. A demand shock leads to an expansion in the elastic college enrollment, depressing the college premium for young workers. With an inelastic supply, experienced college graduates continue to enjoy a rising premium. Despite the low immediate premium, young individuals continue to flood into colleges because they foresee high lifetime returns. Simulations match empirical results well.
Millions of Americans may have asked themselves these questions, or versions of them—especially in the wake of horrific mass shootings like those in Buffalo and Uvalde. Record-breaking spikes in gun sales over the last two years, alongside surveys indicating that self-protection continues to be the dominant reason for buying guns, underscore a widely-held belief that a gun in the home has security benefits.
A new study from my research team, recently published in the Annals of Internal Medicine, shows no such benefits. We found the opposite: people living in homes with guns face substantially higher risks of being fatally assaulted.
Gab was founded in 2016 as an uncensored alternative to mainstream social media platforms. Stanford Internet Observatory’s latest report looks at behaviors and dynamics across the platform.
Topic
This systematic review and meta-analysis summarizes existing evidence to establish whether vision impairment, ocular morbidity and their treatment are associated with depression and anxiety in children.
Clinical Relevance
Understanding and quantifying these associations support early detection and management of mental health symptoms in children with vision impairment and ocular morbidity. Additionally, this review provides evidence in favour of insurance coverage for timely strabismus surgery.
Methods
We searched nine electronic databases from inception to February 18, 2021, including observational and interventional studies assessing whether vision impairment and/or ocular morbidity and their treatment are associated with depression and/or anxiety in children. We used narrative synthesis and meta-analysis with the residual maximum likelihood method. A protocol was registered and published on The International Prospective Register of Systematic Reviews (PROSPERO, CRD42021233323).
Results
Among 28,992 studies, 28,956 (99.9%) were excluded as duplicates or unrelated content. Among 36 remaining studies, 21 (58.3%) were observational studies concerning vision impairment, eight (22.2%) were observational studies concerning strabismus, and seven (19.4%) were interventional studies. Vision-impaired children experienced significantly higher scores of depression (Standard Mean Difference [SMD] 0.57, 95% Confidence Interval (CI) 0.26-0.89, 11 studies) and anxiety (SMD 0.61, 95% CI 0.40-0.821, 14 studies) than normally-sighted children. In particular, myopic children experienced higher scores of depression (SMD 0.59, 95% CI 0.36-0.81, six studies) than normally-sighted children. Strabismus surgery significantly improved symptoms of depression (SMD: 0.59 95% CI 0.12-1.06, three studies) and anxiety (SMD: 0.69 95% CI 0.24-1.14, four studies) in children.
Discussion
Among children, vision impairment is associated with greater symptoms of depression and anxiety. Surgical treatment of strabismus improved these symptoms. Further randomized controlled trials exploring the impact of public health measures for myopia correction on mental health in children are needed. Scaling up access to strabismus surgery could improve the mental health of affected children.
Key policy takeaways from Francis Fukuyama on why Ukraine will win; Jean Oi on U.S.-China climate cooperation; Rose Gottemoeller on nuclear arms control in Europe; Michael McFaul on sanctions and Russia; Larry Diamond on ranked-choice voting; and Renee DiResta on hate speech on social media.
This article examines the consequences of the opium concession system in the Dutch East Indies—a nineteenth-century institution through which the Dutch would auction the monopolistic right to sell opium in a given locality.
Is operating overnight associated with worse outcomes for surgical procedures performed by the attending surgeon the subsequent day? In this cross-sectional study of 498,234 daytime operations performed by 1,131 surgeons at 20 US institutions, there was no significant association between operating the previous night and the incidence of in-hospital death or major complications (sepsis, pneumonia, myocardial infarction, thromboembolic event, or stroke) for daytime operations performed the subsequent day. After adjusting for confounders, the incidence of death or major complications was 5.89% among daytime operations when the attending surgeon operated the night before compared with 5.87% among daytime operations when the attending surgeon did not. These findings suggest that operating overnight does not appear to be associated with worse outcomes when the attending surgeon continues to operate the next day.
A study examining the BRI through the lens of the obsolescing bargain to evaluate the practices of China’s state-owned enterprises (SOEs) and policy banks in mitigating political risk.
International Journal of Environmental Research and Public Health,
May 16, 2022
The objectives of this paper were to examine the risk of depression and depressive symptoms among Han and minority children and adolescents in rural China, the links between academic performance and depressive symptoms, and the prevalence of these links among specific subgroups. A total of 8392 4th, 5th, and 6th grade students at 105 sample rural schools in eight low-income counties and districts in a prefectural-level city in Southwestern China were randomly selected using a three-step sampling strategy. A total of 51% of the sample were female (SD = 0.50), and the age range was 7 to 19 years (mean = 11.35 years; SD = 1.05). Using the Patient Health Questionnaire 8-item depression scale, the prevalence of depressive symptoms in the sample was assessed, while data on students’ academic performance (standardized math test) and demographic characteristics were also collected. Our results show that the rates of major depression were 19% for Han students, 18% for Tibetan students, and 22% for Yi students; the rates of severe depression were 2% for Han and Tibetan students, and 3% for Yi students. Yi students were at significantly higher risks for major and severe depression than Han students. We conducted multivariate regression and heterogeneous analyses. Academic performance was negatively and significantly correlated to depressive symptoms. Across the whole sample, students with lower math scores, minority students, boys, younger students, and students with migrant parents were most vulnerable to depressive symptoms. The heterogeneous analysis suggests that among poor-performing students, subgroups at higher risk for depression include boys, non-boarding students, and students whose mothers had graduated from high school or above. These findings indicate a need to improve mental health outcomes of rural Han and minority primary school students, targeting academic performance for possible intervention.
