We quantify the aggregate implications and distributional consequences of asymmetric information, focusing on the car market. Private information introduces a lemons penalty, a wedge between the sale price and average quality in the population. We estimate an equilibrium model of car ownership with private information using Danish linked registry data on car ownership, income and wealth. In the first year of ownership, the lemons penalty is 11% of the price. The penalty declines sharply with the length of ownership. The penalty leads to large reductions in transaction volumes and in the rate of turnover of cars. But the market does not collapse: income shocks induce individuals to sell their cars, even if of good quality, and this limits the lemons problem. The size of the lemons penalty declines when income uncertainty in the economy increases, as happens in recessions.

Divorce reshapes family life, yet little is known about one of its most consequential features: the allocation of child custody. We study the impact of joint versus sole custody on both parents and children using rich administrative data from Sweden linked to over 25 years of newly-collected court custody rulings. To address selection concerns, we exploit random assignment of custody disputes to judges who differ sharply in their propensity to grant joint custody. For fathers, joint custody substantially raises earnings and improves mental health, consistent with sustained paternal involvement enhancing labor market attachment and psychological well-being. In contrast, there are no measurable labor market or mental health effects for mothers. Turning to children, joint custody increases standardized test scores and school quality without affecting mental health outcomes. Joint custody increases fathers’ chances of remarriage, keeps separated parents in closer geographic proximity, and has no effect on intimate partner violence allegations against either partner. These findings inform longstanding debates over the role of child custody in shaping post-divorce family life. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Childcare services can offer an opportunity for women to develop their careers and increase household income. At the same time, it can affect the development of children, depending on the quality of care. We first develop a collective model of the household as a conceptual framework to show how improving the availability of childcare can affect mothers’ labor market opportunities and earnings and how it can affect child development. We then review the literature on the effects of childcare on the employment and earnings of women and on child development. Childcare can increase mothers’ employment. However, limited work opportunities or strict norms against maternal work can keep mothers out of the labor force. When other family members provide care, childcare can free these caregivers to work or attend school. When studies measure the impact on child development, the results are mixed and depend on both context and quality of provision. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

We build an equilibrium model of a small open economy with labor market frictions and imperfectly enforced regulations. Heterogeneous firms sort into the formal or informal sector. We estimate the model using data from Brazil, and use counterfactual simulations to understand how trade affects economic outcomes in the presence of informality. We show that: (1) Trade openness unambiguously decreases informality in the tradable sector, but has ambiguous effects on aggregate informality. (2) The productivity gains from trade are understated when the informal sector is omitted. (3) Trade openness results in large welfare gains even when informality is repressed. (4) Repressing informality increases productivity, but at the expense of employment and welfare. (5) The effects of trade on wage inequality are reversed when the informal sector is incorporated in the analysis. (6) The informal sector works as an “unemployment,” but not a “welfare buffer” in the event of negative economic shocks.

A number of studies have shown that education reforms extending compulsory schooling reduce criminal behavior of those affected by the reform. We consider the effects of a major Swedish educational reform on crime by exploiting its staggered implementation across Sweden. We first show that the reform reduced crime rates for the generation directly affected by the reform. We then show that the benefits extended to the next generation with large reductions in the crime rates of the children of those affected. The effect operates only through the father and points in the direction of improved parenting rather than resources.

The 1996 PRWORA reform introduced time limits on the receipt of welfare in the United States. We use variation by state and across demographic groups to provide reduced form evidence showing that such limits led to a fall in welfare claims (partly due to “banking” benefits for future use), a rise in employment, and a decline in divorce rates. We then specify and estimate a life-cycle model of marriage, labor supply and divorce under limited commitment to better understand the mechanisms behind these behavioral responses, carry out counterfactual analysis with longer run impacts and evaluate the welfare effects of the program. Based on the model, which reproduces the reduced form estimates, we show that among low educated women, instead of relying on TANF, single mothers work more, more mothers remain married, some move to relying only on food stamps and, in ex-ante welfare terms, women are worse off.

We specify and estimate a rich model of consumption, housing demand and labor supply in an environment where individuals may file for bankruptcy or default on their mortgage. Uncertainty in the model is driven both by house price shocks and income shocks, while bankruptcy is governed by the basic institutional framework in the US as implied by chpater 7 and chapter 13. The model is estimated using micro data on credit reports and mortgages combined with individual level data from the American Community Survey. We perform several counterfactual experiments with the model which investigate welfare aspects of an important reform of the US consumer bankruptcy code implemented in 2006.

We consider risk sharing in rural China during its rapid economic transformation from the late 1980s through the late 2000s. We document an erosion of consumption insurance against both household-level idiosyncratic and village-level aggregate income shocks, and show that this decline is related to observable economic changes: the shift out of agriculture, the decline of publicly owned Township-and-Village Enterprises, and increased migrant work. Further evidence suggests that as these changes took place at the village level, higher levels of government failed to offset these effects through the tax-and-transfer system, leaving households more exposed to both idiosyncratic and village-aggregate risk.

We evaluate impacts heterogeneity of an Early Childhood Intervention in Colombia, with respect to the Educational Attainment Polygenic Score (EA4 PGS) constructed from DNA data based on GWAS weights from a European population. We find that the EA4 PGS is predictive of several measures of child development, mother's IQ and, to some extent, educational attainment. We also show that the impacts of the intervention are significantly greater in children with low PGS, to the point that the intervention eliminates the initial genetic disadvantage. Lastly, we find that children with high PGS attract more parental stimulation; however, the latter increases more strongly in children with low PGS. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial ISRCTN18991160 ### Funding Statement Conti acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 819752 DEVORHBIOSHIP - ERC-2018COG). Jervis gratefully acknowledges financial support from the Institute for Research in Market Imperfections and Public Policy MIPP (ICS13 002 ANID) and the Center for Research in Inclusive Education, Chile (SCIA ANID CIE160009). Meghir thanks the Cowles foundation and the Institution for Social and Policy Studies (ISPS) at Yale for financial support. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics Research Committee of University College London gave ethical approval for this work. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the PI (Orazio Attanasio) upon publication.

Caregiving is a service provided for children with the primary objective of taking care of them and ensuring that they are safe and have opportunities to learn and develop positive relationships with their caregivers and peers while their parents are away. Caregiving takes the forms of home-based care, centre-based care, school-based care, family child care and family, friend, and neighbour (FFN) care. The paper utilises preliminary findings on school attendance from a randomised controlled trial on the effects of a preschool intervention on child learning and women’s economic empowerment in Tharaka Nithi County in school-based care. The research sought to test whether a preschool-based intervention in a rural setting in Kenya influences child development and women’s labour market participation in a cost-effective manner. The project examines the impact of allowing three-year-old children to attend preschool versus the regular pre-primary education programming, which allows children aged 4 years and above to attend preschool. Implementation of the intervention started in January 2024 in 60 intervention schools where five three-year-old children were admitted to a playgroup (PG) in the pre-primary one (PP1) class. Twelve mentors and sixty caregivers were recruited and trained alongside sixty PP1 teachers from the sampled preschools to implement an adapted PP1 curriculum. The twelve mentors coached teachers weekly on the implementation of the curriculum in the five schools assigned to them. This paper presents preliminary findings on preschool attendance for the PG and PP1 children based on weekly attendance data from term one and term two of the 2024 school calendar year on the day the mentors visited the school. Findings reveal that school attendance was low during school openings, midterm breaks, and the last weeks before the schools closed. Public holidays, as well as extracurricular activities coupled with children being sent home for school levies, also contributed to children not attending school regularly. The findings further show that the attendance rate in term one was slightly higher than in term two.

Positive assortative matching refers to the tendency of individuals with similar characteristics to form partnerships. Measuring the extent to which assortative matching differs between two economies is challenging when the marginal distributions of the sorting characteristic (e.g., education) change for either or both sexes. We show how the use of different measures can generate different conclusions. We provide an axiomatic characterization for the odds ratio, normalized trace, and likelihood ratio and provide a structural economic interpretation of the odds ratio. We use our approach to show that marital sorting by education substantially changed between the 1950s and the 1970s cohorts.

Declining labor force participation of older men throughout the 20th century and recent increases in participation have generated substantial interest in understanding the effect of public pensions on retirement. The National Bureau of Economic Research's International Social Security (ISS) Project, a long-term collaboration among researchers in a dozen developed countries, has explored this and related questions. The project employs a harmonized approach to conduct within-country analyses that are combined for meaningful cross-country comparisons. The key lesson is that the choices of policy makers affect the incentive to work at older ages and these incentives have important effects on retirement behavior.

On the basis of a randomized controlled trial, we evaluate a scholarship program in Mexico, Programa de Becas Educaci & oacute;n Media Superior (PROBEMS), aimed at improving graduation rates and test scores among upper secondary school students from poor backgrounds. We find that, on average, the program has no effect on either graduation rates or math and Spanish test scores. We point to two possible reasons for this failure: (i) the program was badly targeted, with many of the recipients being from less disadvantaged families than intended; and (ii) the prior academic achievement of those eligible was often insufficient for successful completion of the academic requirements of upper secondary school. This points to accumulated achievement deficits that could be addressed by interventions targeting learning at an earlier stage.

Social connections are fundamental to human wellbeing. This paper examines the social networks of young married women in rural Odisha, India. This is a group for whom highly-gendered norms around marriage, mobility and work are likely to shape opportunities to form and maintain meaningful ties with other women. We track the social networks of 2,170 mothers over four years, and find a high degree of isolation. Wealthier women and women from more-advantaged castes and tribes have smaller social networks than their less-advantaged peers. These gradients are primarily driven by the fact that more-advantaged women are less likely to know other women within the same socioeconomic group than are less-advantaged women. There exists strong homophily by socioeconomic status (SES) that is symmetric across socioeconomic groups. Mediation analysis shows that SES differences in social isolation are strongly associated with ownership of toilets and labor force participation. Further research should investigate the formation and role of female networks.

Early childhood interventions aim to promote skill acquisition and poverty reduction.While their short-term success is well established, research on longer-term effectiveness is scarce, particularly in LDCs.We present results of a randomized scalable intervention in India, that affected developmental outcomes in the short-term, including cognition (0.36 SD p=0.005), receptive language (0.26 SD p=0.03) and expressive language (0.21 SD p=0.03).After 4.5 years, when the children were on average 7.5 years old, IQ was no longer affected, but impacts persisted relative to the control group in numeracy (0.330 SD, p=0.007) and literacy (0.272 SD, p=0.064) driven by the most disadvantaged.

We develop a money metric welfare index for individuals within households, allowing for public goods, work, and heterogeneous preferences for men and women. Using Japanese data, we estimate a collective model of labor supply, private consumption, and expenditures on children and other public goods. We find that women have stronger preference for spending on children and other public goods than men. Within-household inequality is larger than between-household inequality, but has been declining across cohorts, reflecting improvements in women’s position. This is driven by the increase in women’ college graduation, improvement in their relative wages, and the increase in childcare availability.

Throughout the world, there has been widespread recognition that children’s development is shaped by the cultural context and interactions that begin prenatally and extend throughout childhood.1,2 Children raised in stable and nurturing settings that provide adequate nutrition, responsive caregiving, protection from adversities, and opportunities for learning, along with health and educational services, have the best chance of reaching their full developmental potential.3,4 Nurturing interactions begin with families and extend to community programs and services, including childcare providers, and to policies that shape the macrosocial environment. Children’s early competencies can prepare them to achieve increasingly complex competencies throughout childhood and adolescence, and to become healthy, caring, and productive adults, assuming responsibilities for their family, community, and society. With declines in child mortality5 and fertility over the past 30 years,6 resulting in smaller family sizes, along with increases in early childcare7 and parents’ interest in their young children’s learning opportunities,8 it is not surprising that The World Health Organization and other international organizations regard investments in children as an essential strategy to achieving the United National Sustainable Development Goals.1,9,10Poverty and environmental deprivation disrupt children’s early brain development during periods of neural plasticity and sensitivity to environmental interactions, leading to long-term negative consequences on children’s health and development.11 The effects of poverty on the developing brain are mediated by caregiving behavior and stressful experiences, illustrating the powerful potential of responsive caregiving.12,13In the United States, between 2017 and 2020, 17% of children under 18 years of age (12.6 million children) lived in families with incomes below the poverty line ($26 246 for 2 adults and 2 children).14 Throughout the world, hundreds of millions of children experience poverty and adverse experiences in their communities or households that can disrupt their developmental progress, preventing them from reaching their developmental potential.15 With unrealized human development, children’s ability to escape poverty and build fruitful careers and satisfying lives as adults can be jeopardized. Poverty combined with caregiver stress can undermine children’s exposure to nurturing and developmentally enhancing interactions and opportunities. Globally, it is estimated that over 250 million children under age 5 years are at risk for not meeting their developmental potential.3,16The American Academy of Pediatrics (AAP) is committed to the “optimal physical, mental, and social health and well-being for all infants, children, adolescents, and young adults.”17 AAP’s Council on Early Childhood supports the health and wellbeing of young children; high-quality community-based programs, including childcare, preschool, and parenting programs; and cross-sectoral collaboration to promote community-based early childhood systems. These commitments are backed by both functional and neuroscientific evidence from early child development programs. Research programs, such as the Infant Health and Development Program, an intervention trial among low birth weight, premature infants, show stronger cognitive effects at age 3 years among young children from lower versus higher-income families.18 Based on population projections, income gaps in IQ at age 3 years could be eliminated by programs that are universal or reach children at greatest need.19 Government programs, such as Head Start,20 and programs from nonprofit organizations, such as the Nurse Family Partnership and Parents as Teachers, show positive and sustained effects on children’s cognitive and socio-emotional development and school readiness, particularly among children with few resources.21,22 Building from a strong research base, these programs have been implemented across the country, often with community-based partnerships committed to supporting families and young children.Early childhood development programs have also been developed and implemented in low- and middle-income countries (LMIC). The Jamaica Program developed by Dr. Sally Grantham McGregor and colleagues at the University of the West Indies in the 1970s is a pioneering home visiting program with demonstrated benefits that extend throughout childhood and adolescence, resulting in better employment and higher wages in adulthood.23,24 The Jamaica Program has been translated to “Reach Up Early Childhood Parenting Programme” (https://www.reachupandlearn.com/), known as “Reach Up,” and implemented in at least 16 countries, some at scale. Consistent with the principles of nurturing care,3 Reach Up emphasizes a stable environment that provides protection from threats and opportunities for learning through emotionally supportive and responsive relationships. These experiences have generated insights and lessons on how to effectively implement caregiving intervention programs at scale.Findings from Reach Up,24 Care for Child Development, developed by the World Health Organization and UNICEF,25 and other home visiting programs implemented among infants and young children in low-resource communities demonstrate the powerful impact of early intervention on children’s cognitive and socio-emotional development.26 Guided by bioecological theory and the recognition that children’s development is enhanced with nurturant and responsive caregivers,27,28 early childhood development programs strengthen the capacity of parents and childcare providers to give young children the nurturing care needed to overcome early adversities and reach their developmental potential.7 Longitudinal studies show that the benefits of early intervention can be maintained into adulthood with positive impacts on adult psychological and economic functioning.24,29This supplement originated as a tribute to Professor Sally Grantham-McGregor for her innovative work and commitment to global early childhood development, including the “Order of the British Empire” award for lifetime achievements. The authors of this paper formed a Working Group to organize a supplement dedicated to promoting global early childhood development. We invited over 50 established authors from multiple institutions in high-, middle- and low-income countries to submit concept notes that addressed the implementation of caregiving programs for infants and young children in LMICs. We reviewed 29 concept notes; scored them based on 5 criteria relative to global caregiving interventions (significance, innovation, authors, quality, and potential interest to readers); and invited 20 authors to submit papers or commentaries.We received and reviewed 16 papers and commentaries and invited 14 authors to prepare revised manuscripts for submission. The supplement relies on principles of equity and implementation science to extend beyond impact evaluations and examine topics relevant to scaling intervention programs to reach the children and families in LMICs at greatest need. The papers address topics related to program quality, including children in conflict and other extremely difficult settings, integrating early intervention with other services, delivering services remotely, and partnering with government agencies, among others.The initial commentary is written by Professor Heckman, a Nobel laureate in economics who demonstrated the economic benefits of investing in early childhood development.30 His commentary highlights the central role of the family in building successful pathways for young children. The first paper in the supplement is a meta-analysis of 18 studies across 8 countries that implemented the Reach Up program. Jervis et al found benefits on children’s development and home stimulation across 2 delivery strategies (home visits and small groups), implemented at varying levels of scale.31 This analysis highlights how Reach Up has been successfully implemented across multiple settings and among diverse populations, even as a national program. In the second paper, Hossain et al examined the effects of early childhood intervention among children in Bangladesh after 6 years and found sustained effects of cognitive development among children without a history of anemia.32 The anemic group did not experience benefits either immediately following the intervention or at the 6-year follow-up, suggesting that specialized interventions are necessary for children with specific conditions, such as anemia and disabilities. These findings add to the evidence on the sustainability of early intervention, as well as the harmful effects of anemia. The coronavirus disease 2019 pandemic disrupted many early intervention programs. Smith et al evaluated the development, adaptation, implementation, and impact of a remote version of Reach Up implemented through phone, text, and instant messages among caregivers of young children recruited from health centers in Brazil and Jamaica who met risk criteria.33 Through a mixed methods design, they documented the positive effects of remote delivery of the intervention on caregiving practices.Although there have been multiple calls for integrated interventions,10 few have been implemented. Tofail et al implemented a group-delivered intervention in health facilities in Bangladesh that addressed childhood development, along with maternal mental health.34 Their findings of beneficial effects on multiple domains of children’s development and improvements in mothers’ depressive symptoms and caregiving illustrate the merits of group-delivery of integrated interventions in health facilities. In an innovative design, Meghir et al studied the timing and duration of interventions by comparing children in India randomized to receive interventions delivered before age 3 and/or following age 3.35 Interventions among both age categories benefited children’s IQ and school readiness. The finding that children receiving interventions at both time periods did not experience differential benefits requires additional investigation. The Reach Up program has been implemented among approximately 1500 children in an impoverished region of Western China.36 Zhou et al found that the intervention was successfully implemented at scale, with effect sizes that were comparable to those found among the original Jamaica Program. They note the benefits of starting early and report on program costs.Although the importance of program quality has been well established,37 there has been limited attention to strategies to advance quality. Bernal et al developed quality enhancement to an existing parenting program in rural Colombia and found benefits to childhood development and to caregiving practices, particularly maternal engagement, when quality was high.38 Their observational measure of quality has the potential to promote and maintain intervention quality at scale. In 2019, over 71 million children under age 5 had spent their entire lives in crisis and conflict zones. Based on their experiences of implementing adapted versions of Reach Up in crisis and conflict areas of Bangladesh, Syria, and Venezuela, Wilton et al documented the importance of cultural adaptation of interventions from a holistic perspective of children and caregivers, the inclusion of safety and linkages to complementary services, and incorporating blended models and costing analyses.39Exposure to violence early in life can disrupt children’s brain development, increasing their risk for socio-emotional problems.40 Two papers in the supplement addressed violence prevention. Jensen et al examined associations between intimate partner violence and harsh child discipline in Rwanda.41 They implemented an intervention that reduced harsh discipline by increasing father engagement and parenting warmth among female caregivers, illustrating that violence reduction can be effectively integrated into early childhood development programs to reduce harsh discipline and intimate partner violence. Baker-Henningham et al used implementation science principles in the design, implementation, and scaling of 2 violence-prevention caregiver-training programs for preschoolers in Jamaica: a teacher-training program and a caregiving program.42The final paper in the supplement, by King et al, describes a protocol for a cluster randomized trial to evaluate an integrated, multisector, multiplatform intervention to promote childhood development.43 The intervention targets caregiving behaviors in the home and community, and is delivered in partnership with the Royal Government of Cambodia, illustrating the engagement of local governmental agencies. Recognizing the extension of caregiving from the home to community-based settings, such as childcare, is critical with the global increases in women of child-bearing age participating in the work force.7 The supplement concludes with 2 commentaries. Lombardi et al address the unmet needs of childcare for young children throughout the world and recommend public commitment to childcare, with enhanced infrastructure, innovation, and research.44 In the final commentary, Professors Grantham-McGregor and Walker extend their experiences with the Jamaica Program and Reach Up to discuss strategies to implement caregiving and early intervention programs at scale. In addition to the theoretical and programmatic aspects, they address the need for sustainability and leadership in the field of child development, including training and research that is led by researchers and principal investigators living and working in LMICs.45In summary, the supplement illustrates that early childhood development programs have been advanced and rigorously investigated throughout the world, improving the lives of thousands of young children and offering the potential for designing programs at scale to overcome the effects of poverty and deprivation on children’s development. Similar to programs in the United States, Reach Up and other global intervention programs began as individually oriented home visiting services, recognizing the critical roles of families in nurturing their children’s development. They have expanded and have successfully been delivered using diverse methodologies – including groups, in diverse settings, including health centers, crisis and conflict areas, and remote delivery, consistent with the AAP’s commitment of providing high-quality community-based programs for children. A primary strength of this collection is the inclusion of 79 authors, many of whom are directly involved with research and service within LMICs. A primary limitation is that we may have missed excellent papers by not doing a general call.Future steps in scaling childhood development programs will require attention to the principles of implementation science and the cultural context of communities,46,47 including the commitment to reach children and families at the greatest need; workforce development; accountability; strategies to promote program quality, adaptability, and equity; and finally financial investment, fiscal responsibility, and sustainability. Early childhood development programs have the potential to transform the lives of hundreds of millions of young children, thereby increasing the human capital of countries and promoting the attainment of the United Nations’ Sustainable Development Goals.We thank the New Venture Fund and the Jacobs Foundation for the support of the supplement; the support of the RTI Fellows Program at RTI International to Maureen Black; the contributions of Ana Katrina (Anika) Aquino, M.A. who assisted with the reviews of the manuscripts and the preparation of the manuscripts for submission; the contributions of Joshua Jeong, PhD who assisted with the reviews of the manuscripts; the support of the World Health Organization, UNICEF, the World Bank Group, the Inter-American Development Bank, and other organizations that have supported research into the development of young children throughout the world.