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.
We link industrial clusters, regional productivity and resource reallocation efficiency with geographical and sectoral disaggregated data. Based on a county-industry level panel from 1998 to 2007 in China, we find that industrial clusters significantly increase local industries' productivity by lifting the average firm productivity and reallocating resources from less to more productive firms. Moreover, we find major mechanisms through which resource reallocation is improved within clusters: (i) clusters are associated with a higher firm turnover with increased entry and exit rates simultaneously; and (ii) within clusters' environment, the dispersion of individual firm's markup is significantly reduced, indicating intensified local competition within clusters. Such results suggest that industrial clusters in China help improve regional productivity and resource allocation efficiency with intensified competition and accelerated firm dynamics. The identification issues are carefully addressed by two-stage estimations with instrumental variables and other robustness checks.
Low rates of vaccination, emergence of novel variants of SARS-CoV-2, and increasing transmission relating to seasonal changes and relaxation of mitigation measures leave many US communities at risk for surges of COVID-19 that might strain hospital capacity, as in previous waves. The trajectories of COVID-19 hospitalizations differ across communities depending on their age distributions, vaccination coverage, cumulative incidence, and adoption of risk mitigating behaviors. Yet, existing predictive models of COVID-19 hospitalizations are almost exclusively focused on national- and state-level predictions. This leaves local policymakers in urgent need of tools that can provide early warnings about the possibility that COVID-19 hospitalizations may rise to levels that exceed local capacity. In this work, we develop a framework to generate simple classification rules to predict whether COVID-19 hospitalization will exceed the local hospitalization capacity within a 4- or 8-week period if no additional mitigating strategies are implemented during this time. This framework uses a simulation model of SARS-CoV-2 transmission and COVID-19 hospitalizations in the US to train classification decision trees that are robust to changes in the data-generating process and future uncertainties. These generated classification rules use real-time data related to hospital occupancy and new hospitalizations associated with COVID-19, and when available, genomic surveillance of SARS-CoV-2. We show that these classification rules present reasonable accuracy, sensitivity, and specificity (all ≥ 80%) in predicting local surges in hospitalizations under numerous simulated scenarios, which capture substantial uncertainties over the future trajectories of COVID-19. Our proposed classification rules are simple, visual, and straightforward to use in practice by local decision makers without the need to perform numerical computations.
In each of the three waves of the Section 301 tariffs on Chinese imports, the US government exempted some products on the originally proposed list from additional duties. Using these exempted products as the counterfactual, we identify modest but heterogeneous impacts of the tariffs on the value of US imports from China. We find a complete pass-through for the first and second waves of tariffs. However, unlike in previous studies, we estimate a very limited tariff pass-through of the third wave of tariffs. Finally, we find little import diversion for the US and significant export diversion for China.
Research suggests that elements of the family environment may have significant associations with cognitive and language development outcomes. Less is known, however, about the family environment in peri-urban China, where rates of cognitive and language delay in children aged 0-3 years are as high as 51% and 54%, respectively. Using data collected from 81 peri-urban households with toddlers aged 18-24 months in Southwestern China, this study examines the associations between stimulating parenting practices, the home language environment, and parental self-efficacy, with cognitive and language development. The results indicate that stimulating parenting practices was significantly associated with cognitive development, the home language environment was significantly associated with language development, and parental self-efficacy was significantly associated with cognitive development. The implications of such findings reveal several mechanisms for supporting healthy cognitive and language development among toddlers from peri-urban China.
National Academies of Sciences, Engineering, and Medicine,
January 22, 2023
The COVID-19 pandemic spurred a rapid expansion of wastewater-based infectious disease surveillance systems to monitor and anticipate disease trends in communities.The Centers for Disease Control and Prevention (CDC) launched the National Wastewater Surveillance System in September 2020 to help coordinate and build upon those efforts. Produced at the request of CDC, this report reviews the usefulness of community-level wastewater surveillance during the pandemic and assesses its potential value for control and prevention of infectious diseases beyond COVID-19.
Introduction Millions of young rural children in China still suffer from poor health and malnutrition, partly due to a lack of knowledge about optimal perinatal and child care among rural mothers and caregivers. Meanwhile, there is an urgent need to improve maternal mental health in rural communities. Comprehensive home visiting programmes delivered by community health workers (CHWs) can bridge the caregiver knowledge gap and improve child health and maternal well-being in low-resource settings, but the effectiveness of this approach is unknown in rural China. Additionally, grandmothers play important roles in child care and family decision-making in rural China, suggesting the importance of engaging multiple caregivers in interventions. The Healthy Future programme seeks to improve child health and maternal well-being by developing a staged-based curriculum that CHWs deliver to mothers and caregivers of young children through home visits with the assistance of a tablet-based mHealth system. This protocol describes the design and evaluation plan for this programme.
Methods and analysis We designed a cluster-randomised controlled trial among 119 rural townships in four nationally designated poverty counties in Southwestern China. We will compare the outcomes between three arms: one standard arm with only primary caregivers participating in the intervention, one encouragement arm engaging primary and secondary caregivers and one control arm with no intervention. Families with pregnant women or infants under 6 months of age are invited to enrol in the 12-month study. Primary outcomes include children’s haemoglobin levels, exclusive breastfeeding rates and dietary diversity in complementary feeding. Secondary outcomes include a combination of health, behavioural and intermediate outcomes.
Between 2004 and 2010, Dr. Siegfried Hecker made seven trips to North Korea to explore ways to reduce the danger posed by Pyongyang’s advancing nuclear weapons program.
Autocratic elections are often marred with systematic intimidation and violence toward voters and candidates. When do authoritarian regimes resort to violent electoral strategies?
