The primary goals of food assistance programs are to alleviate child hunger and reduce food insecurity; if successful, such programs may have the added benefit of improving child academic outcomes (e.g., test scores, attendance, behavioral outcomes). Some U.S. government programs serve children in the home, such as the Supplemental Nutritional Assistance Program (SNAP), others serve them at school, such as the National School Lunch Program (NSLP) and School Breakfast Program (SBP), and still others fall in-between, such as the Summer Food Service Program (SFSP) and the Child and Adult Care Food Program (CACFP). Most empirical research seeking to identify the causal effect of such programs on child academic outcomes addresses the endogeneity of program participation with a reduced form, intent-to-treat approach. Specifically, such studies estimate the effect of a program’s availability, timing, or other specific feature on the academic outcomes of all potentially affected children. While findings of individual studies and interventions are mixed, some general conclusions emerge. First, increasing the availability of these programs typically has beneficial effects on relatively contemporaneous academic and behavioral outcomes. The magnitudes are modest but still likely pass cost-benefit criteria, even ignoring the fact that the primary objective of such programs is alleviating hunger, not improving academic outcomes. Less is known about the dynamics of the effects, for example, whether such effects are temporary boosts that dissipate or instead accumulate and grow over time. Likewise, the effects of recent innovations to these programs, such as breakfast in the classroom or increases in SNAP benefits to compensate for reduced time in school during the pandemic, yield less clear conclusions (the former) and/or have not been studied (the latter). Finally, many smaller programs that likely target the neediest children remain under- or un-examined. Unstudied government-provided programs include SFSP and CACFP. There are also a growing number of understudied programs provided primarily by charitable organizations. Emerging evidence suggests that one such program, Weekend Feeding or “Backpack” programs, confers substantial benefits. There, too, more work needs to be done, both to confirm these early findings and to explore recent innovations such as providing food pantries or “Kids’ Cafés” on school grounds. Especially in light of the uncertain fate of many pandemic-related program expansions and innovations, current empirical evidence establishes that the additional, beneficial spillover effects to academic outcomes—beyond the primary objective of alleviating food insecurity—deserve to be considered as well.
The Academic Effects of United States Child Food Assistance Programs—At Home, School, and In-Between
Michael D. Kurtz, Karen Smith Conway, and Robert D. Mohr
Aging and Healthcare Costs
Martin Karlsson, Tor Iversen, and Henning Øien
An open issue in the economics literature is whether healthcare expenditure (HCE) is so concentrated in the last years before death that the age profiles in spending will change when longevity increases. The seminal article “aging of Population and HealthCare Expenditure: A Red Herring?” by Zweifel and colleagues argued that that age is a distraction in explaining growth in HCE. The argument was based on the observation that age did not predict HCE after controlling for time to death (TTD). The authors were soon criticized for the use of a Heckman selection model in this context. Most of the recent literature makes use of variants of a two-part model and seems to give some role to age as well in the explanation. Age seems to matter more for long-term care expenditures (LTCE) than for acute hospital care. When disability is accounted for, the effects of age and TTD diminish. Not many articles validate their approach by comparing properties of different estimation models. In order to evaluate popular models used in the literature and to gain an understanding of the divergent results of previous studies, an empirical analysis based on a claims data set from Germany is conducted. This analysis generates a number of useful insights. There is a significant age gradient in HCE, most for LTCE, and costs of dying are substantial. These “costs of dying” have, however, a limited impact on the age gradient in HCE. These findings are interpreted as evidence against the red herring hypothesis as initially stated. The results indicate that the choice of estimation method makes little difference and if they differ, ordinary least squares regression tends to perform better than the alternatives. When validating the methods out of sample and out of period, there is no evidence that including TTD leads to better predictions of aggregate future HCE. It appears that the literature might benefit from focusing on the predictive power of the estimators instead of their actual fit to the data within the sample.
Anthropometrics: The Intersection of Economics and Human Biology
Anthropometrics is a research program that explores the extent to which economic processes affect human biological processes using height and weight as markers. This agenda differs from health economics in the sense that instead of studying diseases or longevity, macro manifestations of well-being, it focuses on cellular-level processes that determine the extent to which the organism thrives in its socio-economic and epidemiological environment. Thus, anthropometric indicators are used as a proxy measure for the biological standard of living as complements to conventional measures based on monetary units. Using physical stature as a marker, we enabled the profession to learn about the well-being of children and youth for whom market-generated monetary data are not abundant even in contemporary societies. It is now clear that economic transformations such as the onset of the Industrial Revolution and modern economic growth were accompanied by negative externalities that were hitherto unknown. Moreover, there is plenty of evidence to indicate that the Welfare States of Western and Northern Europe take better care of the biological needs of their citizens than the market-oriented health-care system of the United States. Obesity has reached pandemic proportions in the United States affecting 40% of the population. It is fostered by a sedentary and harried lifestyle, by the diminution in self-control, the spread of labor-saving technologies, and the rise of instant gratification characteristic of post-industrial society. The spread of television and a fast-food culture in the 1950s were watershed developments in this regard that accelerated the process. Obesity poses a serious health risk including heart disease, stroke, diabetes, and some types of cancer and its cost reaches $150 billion per annum in the United States or about $1,400 per capita. We conclude that the economy influences not only mortality and health but reaches bone-deep into the cellular level of the human organism. In other words, the economy is inextricably intertwined with human biological processes.
A Review of the Effects of Pay Transparency
Emma Duchini, Stefania Simion, and Arthur Turrell
An increasing number of countries have introduced pay transparency policies with the aim of reducing gender inequality in the labor market. Firms subject to transparency requirements must disclose publicly or to employees’ representatives information on their employees’ pay broken down by gender, or indicators of gender gaps in pay and career outcomes. The argument at the base of these policies is that gender inequality may in part persist because it is hidden. On the one hand, employers rarely keep track of employees’ pay and career progression by gender, and, on the other hand, employees rarely engage in conversations with their colleagues about pay. The lack of information on within-firm disparities by gender may therefore hamper progress toward a more egalitarian labor market. Transparency policies have the potential to improve women’s relative pay and career outcomes for two reasons. First, by increasing the salience of gender gaps in the labor market, they can alter the relative bargaining power of male and female employees vis-à-vis the firm and lead lower-paid individuals to demand higher pay from their employer. Second, together with pressures from employees, the public availability of information on firms’ gender-equality performance may also increase public pressure for firms’ action in this domain. A clear message emerges from the literature analyzing the impact of pay transparency policies on gender inequality: these policies are effective at pushing firms to reduce their gender pay gaps, although this is achieved via a slowdown of men’s wage growth. Related results point to a reduction in labor productivity following the introduction of transparency mandates but no detrimental effect on firms’ profits because this effect is compensated by the reduction in labor costs. Overall, the findings in this literature suggest that transparency policies can reduce the gender pay gap with limited costs for firms but may not be suited to achieve the objective of improving outcomes for lower-paid employees.
Business Cycles and Apprenticeships
Samuel Muehlemann and Stefan Wolter
The economic reasons why firms engage in apprenticeship training are twofold. First, apprenticeship training is a potentially cost-effective strategy for filling a firm’s future vacancies, particularly if skilled labor on the external labor market is scarce. Second, apprentices can be cost-effective substitutes for other types of labor in the current production process. As current and expected business and labor market conditions determine a firm’s expected work volume and thus its future demand for skilled labor, they are potentially important drivers of a firm’s training decisions. Empirical studies have found that the business cycle affects apprenticeship markets. However, while the economic magnitude of these effects is moderate on average, there is substantial heterogeneity across countries, even among those that at first sight seem very similar in terms of their apprenticeship systems. Moreover, identification of business cycle effects is a difficult task. First, statistics on apprenticeship markets are often less developed than labor market statistics, making empirical analyses of demand and supply impossible in many cases. In particular, data about unfilled apprenticeship vacancies and unsuccessful applicants are paramount for assessing potential market failures and analyzing the extent to which business cycle fluctuations may amplify imbalances in apprenticeship markets. Second, the intensity of business cycle effects on apprenticeship markets is not completely exogenous, as governments typically undertake a variety of measures, which differ across countries and may change over time, to reduce the adverse effects of economic downturns on apprenticeship markets. During the economic crisis related to the COVID-19 global pandemic, many countries took unprecedented actions to support their economies in general and reacted swiftly to introduce measures such as the provision of financial subsidies for training firms or the establishment of apprenticeship task forces. As statistics on apprenticeship markets improve over time, such heterogeneity in policy measures should be exploited to improve our understanding of the business cycle and its relationship with apprenticeships.
Corporate Takeovers and Non-Financial Stakeholders
Daniel Greene, Omesh Kini, Mo Shen, and Jaideep Shenoy
A large body of work has examined the impact of corporate takeovers on the financial stakeholders (shareholders and bondholders) of the merging firms. Since the late 2000s, empirical research has increasingly highlighted the crucial role played by the non-financial stakeholders (labor, suppliers, customers, government, and communities) in these transactions. It is, therefore, important to understand the interplay between corporate takeovers and the non-financial stakeholders of the firm. Financial economists have long viewed the firm as a nexus of contracts between various stakeholders connected to the firm. Corporate takeovers not only play an important role in redefining the broad boundaries of the firm but also result in major changes to corporate ownership and structure. In the process, takeovers can significantly alter the contractual relationships with non-financial stakeholders. Because the firm’s relationships with these stakeholders are governed by implicit and explicit contracts, circumstances can arise that allow acquiring firms to fully or partially abrogate these contracts and extract rents from non-financial stakeholders after deal completion. In contrast, non-financial stakeholders can also potentially benefit from a takeover if they get to share in any efficiency gains that are generated in the deal. Given this framework, the ex-ante importance of these contractual relationships can have a bearing on the efficacy of takeovers. The ability to alter contractual relationships ex post can affect the propensity of a takeover and merging firms’ shareholders and, in turn, impact non-financial stakeholders. Non-financial stakeholders will be more vested in post-takeover success if they can trust the acquiring firm to not take actions that are detrimental to them. The big picture that emerges from the surveyed literature is that non-financial stakeholder considerations affect takeover decisions and post-takeover outcomes. Moreover, takeovers also have an impact on non-financial stakeholders. The directions of all these effects, however, depend on the economic environment in which the merging firms operate.
Creative Destruction, Technology Disruption, and Growth
The origins of modern technological change provide the context necessary to understand present-day technological transformation, to investigate the impact of the new digital technologies, and to examine the phenomenon of digital disruption of established industries and occupations. How these contemporary technologies will transform industries and institutions, or serve to create new industries and institutions, will unfold in time. The implications of the relationships between these pervasive new forms of digital transformation and the accompanying new business models, business strategies, innovation, and capabilities are being worked through at global, national, corporate, and local levels. Whatever the technological future holds it will be defined by continual adaptation, perpetual innovation, and the search for new potential. Presently, the world is experiencing the impact of waves of innovation created by the rapid advance of digital networks, software, and information and communication technology systems that have transformed workplaces, cities, and whole economies. These digital technologies are converging and coalescing into intelligent technology systems that facilitate and structure our lives. Through creative destruction, digital technologies fundamentally challenge existing routines, capabilities, and structures by which organizations presently operate, adapt, and innovate. In turn, digital technologies stimulate a higher rate of both technological and business model innovation, moving from producer innovation toward more user-collaborative and open-collaborative innovation. However, as dominant global platform technologies emerge, some impending dilemmas associated with the concentration and monopolization of digital markets become salient. The extent of the contribution made by digital transformation to economic growth and environmental sustainability requires a critical appraisal.
Dual Labor Markets Revisited
Samuel Bentolila, Juan J. Dolado, and Juan F. Jimeno
This article provides an overview of empirical and theoretical research on dual labor markets. It revisits the labor-market effects of dual employment protection legislation as well as the main factors behind its resilience. Characterized by a high incidence of temporary contracts, which may lead to stepping-stone or dead-end jobs, dual labor markets exhibit specific features regarding the determination of employment, unemployment, churn, training, productivity growth, wages, and labor market flows. Relying on the contrasting experiences of several OECD countries with different degrees of duality and, in particular, on the very poor employment performance of some EU countries during the Great Recession, lessons are drawn about policy-reform strategies aiming to correct the inefficiencies of dual labor markets.
The Early Origins of the Civil Rights Movement in the United States: An Analysis of the Growth of the NAACP
Daniel Aaronson, Jala Abner, Mark Borgschulte, and Bhashkar Mazumder
A newly digitized panel of county-level branch activity of the National Association for the Advancement of Colored People (NAACP) is used to describe the potential factors underlying the expansion of political participation in the American South, with a particular emphasis on the short period from the late 1930s through the 1940s. This period has long been recognized for its significant progress in reducing sizable racial gaps in labor market outcomes. But little work in economics has considered the role of political participation in shaping that progress. As the preeminent civil rights organization prior to the 1950s, the NAACP provides a natural lens in which to explore the expansion in political activism during this crucial period. Associative evidence suggests that a few potential channels could be especially worthy of future study, including the role of demographics, increased human capital, expansion in labor demand driven by wartime efforts, reduction in racial violence, latent political activism, and expansions in political and social networks, all of which have been highlighted in a variety of history and social science literatures. However, careful causal empirical work does not currently exist on these factors. Filling in this hole is important for providing compelling evidence on the origins of the 20th century’s most important U.S. political movement, as well as adding to a growing literature in political economy and development economics which examines the role that grassroots activism has played on economic growth and income inequality around the world.
Earnings Inequality in Latin America: A Three-Decade Retrospective
Manuel Fernández and Gabriela Serrano
Latin American countries have some of the highest levels of income inequality in the world. However, earnings inequality have significantly changed over time, increasing during the 1980s and 1990s, declining sharply in the 2000s, and stagnating or even increasing in some countries since 2015. Macroeconomic instability in the region in the 1980s and early 1990s, as well as the introduction of structural reforms like trade, capital, and financial liberalization, affected the patterns of relative demand and relative earnings across skill-demographic groups in the 1990s, increasing inequality. Significant gains in educational attainment, the demographic transition, and rising female labor force participation changed the skill-demographic composition of labor supply, pushing the education and experience premiums downward, but this was not enough to counteract demand-side trends. At the turn of the 21st century, improved external conditions, driven by China’s massive increase in demand for commodities, boosted economies across Latin America, which began to grow rapidly. Growth was accompanied by a positive shift in the relative demand for less-educated workers, stronger labor institutions, rising minimum wages, and declining labor informality, a confluence of factors that reduced earnings inequality. In the aftermath of the global financial crisis, particularly after the end of the commodities price boom in 2014, economic growth decelerated, and the pace of inequality decline stagnated. There is extensive literature documenting and trying to explain the causes of recent earnings inequality dynamics in Latin America. This literature is examined in terms of themes, methodological approaches, and key findings. The focus is on earnings inequality and how developments in labor markets have shaped it.
The Economic Effect of Vocational Education on Student Outcomes
Shaun M. Dougherty and Walter G. Ecton
As long as formal education has existed, there has been a clear connection between education and preparation for employment. In much of the world, formal educational systems have come to include vocational education and training (VET) as part of secondary education. In these spaces, individuals can receive continued training in general skills related to reading, writing, and mathematics while also pursuing specific skills in prescribed vocational or technical programs (e.g., skilled trades, culinary arts, information technology, health services). Across all countries and associated educational systems, a tension exists between whether to invest educational dollars in general versus specific skill development. On the one hand, general skills allow for transferability and likely support adaptability across workplace settings and in response to changes in employment conditions. On the other hand, secondary school completion is not universal, even in rich countries, and there are often large penalties or social costs to not completing secondary education. Furthermore, across countries of varying GDP levels, the question about how to best prepare individuals for entry into and success in the workforce is a persistent one. Evidence suggests that the payoff to investments in VET vary considerably, and that context and the characteristics of participants likely inform the expected returns to such investments. For instance, there is strong evidence across contexts that male participants in VET are likely to benefit in the short- to medium-term with respect to employment and earnings, and possibly also engage in less crime. Unresolved, however, is whether these payoffs persist in the longer term. In contrast, for women the estimated returns appear to be more context dependent. Some research shows reduced fertility and greater financial independence of women participating in VET programs in less-developed countries, but evidence is mixed in other settings. All evidence underscores that the payoff to VET is likely tied to the extent to which it adapts to contemporary economic needs, including extending the amount of total formal education that participants might otherwise receive.
Economics and Family Structures
Thomas Baudin, Bram De Rock, and Paula Gobbi
Household decisions are one of the key elements impacting many dimensions of any economy. For instance at the macro level, decisions regarding how much to save affect the economy’s investment possibilities or decisions regarding children’s education affect the overall level of human capital. Economists who study household behavior have almost solely focused on the understanding of nuclear families, i.e., parents living with their own children, childless couples, or singles. However, it is well documented that family types are heterogeneous across and within countries, both in the past and in present times. Among the different types, a classical distinction can be made between nuclear, stem, and complex households. Stem families are those allowing for three generations to live in a same household. Complex families allow for several married siblings to live together in a household. It is important to note that this is not a marginal phenomenon. For instance in China or India, the two most populous countries in the world, the majority of the population lives in either stem or complex families types. However, there is still a lot to understand about them. What are the driving factors leading individuals to form one type of family over another? Are these drivers economic or cultural? What are the intra-household dynamics of these families and how do they function? What are the implications of these differences for implementing effective family policies? The focus on nuclear families limits our capacity to answer these questions and to analyze the impact of institutional phenomena or public policies. More research to understand the determinants and functioning of other types of families hence matters both from an academic and a policy perspective.
Economics and Genetics
Jason M. Fletcher
Two interrelated advances in genetics have occurred which have ushered in the growing field of genoeconomics. The first is a rapid expansion of so-called big data featuring genetic information collected from large population–based samples. The second is enhancements to computational and predictive power to aggregate small genetic effects across the genome into single summary measures called polygenic scores (PGSs). Together, these advances will be incorporated broadly with economic research, with strong possibilities for new insights and methodological techniques.
The Economics of Families and Health
Susan Averett and Jennifer Kohn
An individual’s health is produced in large part by family investments that start before birth and continue to the end of life. The health of an individual is intertwined with practically every economic decision including education, marriage, fertility, labor market, and investments. These outcomes in turn affect income and wealth and hence have implications for intergenerational transfer of economic advantage or disadvantage. A rich body of theoretical and empirical work considers the role of the family in health production over the life cycle and the role of health in household economic decisions. This literature starts by considering family inputs regarding health at birth, then moves through adolescence and midlife, where relationship decisions affect health. After midlife, health, particularly the health of family members, becomes an input into retirement and investment decisions. The literature on family and health showcases economists’ skills in modeling complex family dynamics, deriving theoretical predictions, and using clever econometric strategies to identify causal effects.
The Economics of Informal Care
Courtney Van Houtven, Fiona Carmichael, Josephine Jacobs, and Peter C. Coyte
Across the globe, the most common means of supporting older disabled adults in their homes is through “informal care.” An informal carer is a family member or friend, including children or adults, who help another person because of their illness, frailty, or disability. There is a rich economics literature on the direct benefits of caregiving, including allowing the care recipient to remain at home for longer than if there was no informal care provided. There is also a growing literature outlining the associated costs of care provision. Although informal care helps individuals with disabilities to remain at home and is rewarding to many carers, there are often negative effects such as depression and lost labor market earnings that may offset some of these rewards. Economists have taken several approaches to quantify the net societal benefit of informal care that consider the degree of choice in caregiving decisions and all direct and indirect benefits and costs of informal care.
Economics of Rural–Urban Migration
Pei-Ju Liao and Chong Kee Yip
In the past century, many developing countries have experienced rapid economic development, which is usually associated with a process of structural transformation and urbanization. Rural–urban migration, shifting the labor force from less productive agricultural sectors to more productive industrial sectors in cities, plays an important role in the growth process and thus has drawn economists’ attention. For instance, it is recognized that one of the important sources of China’s growth miracle is rural–urban migration. At the early stage of economic development, an economy usually relies on labor-intensive industries for growth. Rural–urban migrants thus provide the necessary labor force to urban production. Since they are more productive in industrial sectors than in agricultural sectors, aggregate output increases and economic growth accelerates. In addition, abundant migrants affect the rates of return to capital by changing the capital–labor ratio. They also change the skill composition of the urban labor force and hence the relative wage of skilled to unskilled workers. Therefore, rural–urban migration has wide impacts on growth and income distribution of the macroeconomy. What are the forces that drive rural–urban migration? It is well understood that cities attract rural migrants because of better job opportunities, better career prospects, and higher wages. Moreover, enjoying better social benefits such as better medical care in cities is another pull factor that initiates rural–urban migration. Finally, agricultural land scarcity in the countryside plays an important role on the push side for moving labor to cities. The aforementioned driving forces of rural–urban migration are work-based. However, rural–urban migration could be education-based, which is rarely discussed in the literature. In the past decade, it has been proposed that cities are the places for accumulating human capital in work. It is also well established that most of the high-quality education institutions (including universities and specialized schools for art and music) are located in urban areas. A youth may first move to the city to attend college and then stay there for work after graduation. From this point of view, work-based migration does not paint the whole picture of rural–urban migration. In this article, we propose a balanced view that both the work-based and education-based channels are important to rural–urban migration. The migration story could be misleading if any of them is ignored.
Economic Theory of Criminal Law
Keith N. Hylton
Criminal law consists of substantive and procedural parts. Substantive law is the set of rules defining conduct that violates the law. Procedural criminal law is the set of rules regulating the process of punishment. Substantive rules apply mostly to individual actors, and procedural rules apply to public enforcement agencies and adjudicators. Economic theory of criminal law consists of normative and positive parts. Normative economic theory, which began with writings by Beccaria and Bentham, aims to recommend an ideal criminal punishment scheme. Positive economic theory, which appeared later in writings by Holmes and Posner, aims to justify and to better understand the criminal law rules that exist. Since the purpose of criminal law is to deter socially undesirable conduct, economic theory, which emphasizes incentives, would appear to be an important perspective from which to examine criminal law. Positive economic theory, applied to substantive criminal law, seeks to explain and to justify criminal law doctrine in economic terms—that is, in terms that emphasize the incentive effects created by the law. The positive economic theory of criminal law literature can be divided into three phases: Classical deterrence theory, neoclassical deterrence, and modern synthesis. The modern synthesis provides a rationale for fundamental criminal law doctrines and also more puzzling portions of the law such as the doctrines of intent and necessity. Positive economic theory also provides a rationale for the allocation of enforcement responsibilities.
Education and Economic Growth
Eric A. Hanushek and Ludger Woessmann
Economic growth determines the future well-being of society, but finding ways to influence it has eluded many nations. Empirical analysis of differences in growth rates reaches a simple conclusion: long-run growth in gross domestic product (GDP) is largely determined by the skills of a nation’s population. Moreover, the relevant skills can be readily gauged by standardized tests of cognitive achievement. Over the period 1960–2000, three-quarters of the variation in growth of GDP per capita across countries can be accounted for by international measures of math and science skills. The relationship between aggregate cognitive skills, called the knowledge capital of a nation, and the long-run growth rate is extraordinarily strong. There are natural questions about whether the knowledge capital–growth relationship is causal. While it is impossible to provide conclusive proof of causality, the existing evidence makes a strong prima facie case that changing the skills of the population will lead to higher growth rates. If future GDP is projected based on the historical growth relationship, the results indicate that modest efforts to bring all students to minimal levels will produce huge economic gains. Improvements in the quality of schools have strong long-term benefits. The best way to improve the quality of schools is unclear from existing research. On the other hand, a number of developed and developing countries have shown that improvement is possible.
Education and Social Mobility
Helena Holmlund and Martin Nybom
Family background is a strong determinant of an individual’s educational achievement and labor market success. Using an economics framework, intergenerational persistence in socioeconomic status can be explained by a variety of factors, including parental investment behavior, credit constraints, and the degree of inequality in society. Genetic transmission from parents to children may also play a role. In addition, the skill formation process is governed by dynamics between different stages of a child’s life, such as complementarities between early and late investments or between informal and formal education. Education policy holds the promise of breaking the strong ties between family background and socioeconomic position by providing publicly accessible education for children of all backgrounds. However, the education system may also perpetuate social inequalities if well-off families are able to protect their children from downward mobility by, for example, moving to neighborhoods with high-quality schools and by providing networks that offer opportunities to succeed. However, a growing number of studies show that educational interventions can have long-lasting effects on students’ outcomes, in particular for disadvantaged students, and that they can be cost-effective. For example, reducing class size, increasing general education spending, tutoring, and improving teacher quality are policy levers that are shown to be successful in this regard. Shifting from selective to comprehensive school systems is also a policy that enhances equality of opportunity. While the evidence on credit constraints and their role for access to higher education is evolving, but still mostly U.S. focused and largely inconclusive, it is a key domain for shaping social mobility given the life-changing impacts that a university degree can have.
The Effect of Immigration on Education
Does a higher share of immigrants affect the school performance of both immigrants and natives? Do desegregation policies improve efficiency? The existing evidence suggests that a higher share of immigrants has a negative (and often sizable) effect on the school performance of immigrants and a negative but probably small effect on the performance of natives. When average school performance is considered, this asymmetry generates concave peer effects, a key condition for the efficiency of desegregating policies. The broad message from the empirical literature is that these policies are not only equitable, in that they provide better opportunities to individuals with relatively low parental background, but also efficient.