Across many disciplines, the fixed effects estimator of linear panel data models is the default method to estimate causal effects with nonexperimental data that are not confounded by time-invariant, unit-specific heterogeneity. One feature of the fixed effects estimator, however, is often...

We study the treatment effect of grade retention, using a panel of French junior highschool students, taking unobserved heterogeneity and the endogeneity of grade repetitions into account. We specify a multi-stage model of human-capital accumulation with a finite number of types representing...

The literature that tests for U-shaped relationships using panel data, such as those between pollution and income or inequality and growth, reports widely divergent (parametric and non-parametric) empirical findings. We explain why lack of identification lies at the root of these differences. To...

The production and diffusion of knowledge have increasingly been seen as potential causes of the observed international differences in total factor productivity and, in turn, as possible sources of economic growth. This paper presents the results of a causality study between business visits and...

This paper develops a nonparametric methodology for treatment evaluation with multiple outcome periods under treatment endogeneity and missing outcomes. We use instrumental variables, pre-treatment characteristics, and short-term (or intermediate) outcomes to identify the average treatment...