This dissertation's idea began with my class notes and questions in the statistics courses I attended in my doctoral program. These notes and questions originally were about the concepts of the bell shape, statistical distribution, and hypothesis testing. They then became my inquiries of p-values because what I learned in the courses about how the…

This work comprises studies on the effects of broadband Internet in schools at three different levels: student performance, household Internet adoption, and individual computer and Internet use patterns and skill acquisition. I focus in the case of Portugal, where by 2006 the Portuguese government had completed a major initiative that upgraded the…

Effective policymaking requires understanding the causal effects of competing proposals. Relevant causal quantities include proposals' expected effect on different groups of recipients, the impact of policies over time, the potential trade-offs between competing objectives, and, ultimately, the optimal policy. This dissertation studies causal…

The first chapter studies the effects of a teacher performance bonus program implemented in Brazil in 2008. The program covered all schools directly managed by the State of Sao Paulo government, and was based on a standardized test run by the state education authority. I use high-school exit exams organized by the federal government (ENEM) to…