We show that the usual inference methods used in Di fferences-in-Di fferences (DID) might not perform well with few treated groups and heteroskedastic errors. One important example is when there is variation in the number ...

In 1997, Brazil approved law n(cr) 9478, establishing new rules for sharing petroleum royalties with Brazilian municipalities. The goal of this paper is to evaluate whether royalties distributed under the new law have ...

Differences-in-Differences (DID) is one of the most widely used identification strategies in applied economics. However, how to draw inferences in DID models when there are few treated groups remains an open question. We ...

We use time-series and cross-section variation in adoption of dry laws in the São Paulo Metropolitan Area (SPMA) to measure the impact of recreational consumption of alcohol on violent behavior. Adoption of dry laws causes ...

We propose a locally efficient estimator for a class of semiparametric data combination problems. A leading estimand in this class is the average treatment effect on the treated (ATT). Data combination problems are related ...

This paper aims to assess the short run effects of the More Doctors Program, launched by the Brazilian federal government in 2013. Using differences-in-differences approach with municipal data collected between 2010 and ...

This paper presents evidence of the effect of the recent phases of the business cycle in Spain and United States, proxied by their respective unemployment rates, on the labor market of Colombian cities with high migration ...

Sperm migration in estrous cervical mucus can be used to measure the ability of spermatozoa to migrate through the genital tract, The relationship of this test with the sperm colonization of the isthmus, and its impact on ...