We document substantial variation in the effects of a highly-effective literacy program in northern Uganda. The program increases test scores by 1.40 SDs on average, but standard statistical bounds show that the impact standard deviation exceeds 1.0 SD. This implies that the variation in effects across our students is wider than the spread of mean effects across all randomized evaluations of developing country education interventions in the literature. This very effective program does indeed leave some students behind. At the same time, we do not learn much from our analyses that attempt to determine which students benefit more or less from the program. We reject rank preservation, and the weaker assumption of stochastic increasingness leaves wide bounds on quantile-specific average treatment effects. Neither conventional nor machine-learning approaches to estimating systematic heterogeneity capture more than a small fraction of the variation in impacts given our available candidate moderators

We examine how residential property values are impacted by school shootings, which are crimes that have a very low probability of being repeated in the same location. We exploit the exogenous timing of eleven mass shootings that took place between 1998 and 2014,  and use a difference-in-differences framework to estimate the causal effect of these school shootings on property values in the affected school attendance area. We find that house prices decline by an average of around 2.4 percent in a four-year period after a mass school shooting. We also find that enrollment falls in the affected school district, suggesting that families subsequently avoid schools in areas that have experienced such events.

The literature that has previously shown that boys outperform girls in math tests has failed to explain the underlying causes of the phenomenon. This math gender gap has been documented to vary across countries, and shown to grow as students advance through school. In this paper I suggest that these patterns may be explained by sample selection caused by gender differences in schooling's opportunity costs, which lead lower-achieving males to drop out. I present and test the implications of a labor supply model that examines the opportunity cost of school attendance and, thereby, the observed math gender gap. Using an exogenous policy change, the launch of a conditional cash transfer program in Colombia, I estimate that sample selection explains between 50 percent and 60 percent of the gap. Estimates of non-parametric bounds show that selection in the lower quantiles of the male distribution explains a significant portion of the gap.

We use 292 household surveys from eighteen Latin American countries to document patterns in secondary school graduation rates over the period 1990–2010. We find that enrollment and graduation rates increased during that period, while dropout rates decreased. We provide two types of explanations for these patterns. Countries implemented changes on the supply side to improve access, by increasing the resources allocated to education and designing policies to help students stay in school. Despite this progress, graduation rates are still generally low, and there are remarkable gaps in educational outcomes in terms of gender, income quintiles, and regions within countries. The quality of education is also generally low. 

We study how signaling skills that are specific to college majors affect labor market outcomes of college graduates. We rely on census-like data and a regression discontinuity design to study the impacts of a well-known award given to top performers on a mandatory nationwide exam in Colombia. The award allows students to signal their high level of specific skills when searching for a job. These students earn 7 to 12 percent more than otherwise identical students lacking the signal. This positive return persists five years after graduation. The signal mostly benefits workers who graduate from low-reputation colleges, and allows workers to find jobs in more productive firms and in sectors that better use their skills. We rule out that the positive earnings returns are explained by human capital. The signal favors mostly less advantaged groups, implying that reducing information frictions about students' skills could potentially shrink earnings gaps. Our results imply that information policies like those that formally certify skills can improve the efficiency in talent allocation of the economy and, at the same time, level the playing field.

We study how import competition and foreign inputs coming from high-income countries affect  employment and earnings in less-developed economies. We use administrative data  from  Colombia,  and  exploit  exogenous  tariff  reductions  that  increased  Colombian imports  from  the  United States. Import competition decreases employment in a similar magnitude than foreign inputs increase it.  The adverse employment effects of import competition are driven by firm exit. Foreign inputs  increase non-college educated employment in services by inducing firm entry, but decrease employment in manufacturing by substituting labor demand. Both shocks reduce earnings among college-educated, informal workers. Our results contrast with findings  for high-income  economies.

• • • Previously circulated as: Entering the Major Leagues: The Effect of Competition from the United States on Workers and Firms in an Emerging Economy

Teacher quality is a key factor in improving student academic achievement. As such, education policymakers design screening systems to hire the most effective teachers. In this paper, we study the effects of introducing a centralized merit-based screening system for all Colombian public schools that ties teacher hiring decisions to candidates' performance on an exam evaluating subject-specific knowledge and teaching aptitude. This policy had the intended result of increasing the pre-college test scores of teachers by 17 percentile points. However, it also unintentionally decreased the overall stock of teacher experience in public schools. Using a difference-in-differences strategy that compares the outcomes of students from public and private schools over two decades, we find that instead of improving student outcomes, this screening system decreased students' performance on high school exit exams by 8 percent of a standard deviation, and reduced the likelihood of enrolling and graduating from college by over 10 percent. These results suggest that relying exclusively on ex-ante teacher quality measures to screen teacher candidates may have a limited effect on students' achievement.

This paper shows that returns to education are not enough to capture all the returns to human capital. Using longitudinal data of all college graduates in Colombia, we estimate labor market returns to postsecondary degrees and to various skills --including literacy, numeracy, foreign language, field-specific, and non-cognitive skills. Graduates of longer programs, of private institutions, and of schools with higher reputation earn higher wages. Even after controlling for all the characteristics of the degree, a one standard deviation increase in each skill predicts an average wage increase of two percent. Returns to skills vary along the wage distribution, with tenure, with the field of specialization and the type of job obtained immediately after graduation.

We estimate the long-term effects of a program that provided alternative delivery methods of conditional cash transfers in Bogotá, Colombia. We evaluate the effects on a rich array of education and labor market outcomes, and extend the analysis to include the spillover effects of the program on beneficiaries and their family members. We specifically estimate the education and labor market effects on parents and siblings of treated students. By definition these parents and siblings were not treated but they could have benefit for the money transfer to one of their household members. We rely on a randomized control trial that allocated the program at random to children among a set of families with eligible students. 

We study the differential effects of migration by suggesting a novel hypothesis that reconciles pre-existing contradictory evidence of the effects of migrants on local communities. Our hypothesis relates the effects of migration to the migrants' cost of not migrating (i.e. the opportunity cost of migration), and suggests that the consequences of migration vary depending on the migrants' incentives to migrate. Most of the negative effects of migrants are usually driven by the their willingness to accept lower paid jobs, but the incentives to migrate depend on the opportunity cost (i.e. the benefit received by not migrating), which varies between several types of migrants. It is expected that migrants with low opportunity cost of relocating (or less incentives to stay in their origin) accept lower paid others (including joining illegal activities), whereas migrants with a higher opportunity cost will not.

This project received funding by LEM and is it in the process of data collection.