Nationwide health interventions are difficult to evaluate as contemporaneous control groups do not exist and before-after approaches are usually infeasible. We propose an alternative semi-parametric estimator that is based on the assumption that the intervention has no direct effect on the...

This paper proposes a difference-in-differences approach for disentangling a total treatment effect on some outcome into a direct impact as well as an indirect effect operating through a binary intermediate variable - or mediator - within strata defined upon how the mediator reacts to the...

Economic theory predicts that adverse shocks during early childhood have detrimental short- and long-run consequences for children's development. We examine this hypothesis by analyzing the short-and long-run effects on children's health and education of a specific shock: housing damages caused...

This paper studies the role of job search assistance programs in optimal welfare-to-work programs. The analysis is based on a framework, that allows for endogenous choice of benefit types and levels, wage taxes or subsidies, and activation measures such as monitoring and job search assistance...

We provide new evidence on the effectiveness of West German labour market programmes by evaluating training and employment programmes that have been conducted 2000 - 2002 after the first large reform of German labour market policy in 1998. We employ exceptionally rich administrative data that...

Labour market policies for the unemployed combine passive income support with active measures that aim at improving jobseekers' employment prospects. This paper extends the theoretical framework developed by Pavoni and Violante (2005a) for the optimal choice between different active and passive...

In this study we experimentally investigate whether solidarity, which is a crucial base for informal insurance arrangements in developing countries, is sensitive to the extent to which in-dividuals can influence their risk exposure. With slum dwellers of Nairobi our design measures subjects'...

Negative income shocks can either be the consequence of risky choices or random events. A growing literature analyzes the role of responsibility for neediness for informal financial support of individuals facing negative income shocks based on randomized experiments. In this paper, we show that...

Understanding the mechanisms through which treatment effects come about is crucial for designing effective interventions. The identification of such causal mechanisms is challenging and typically requires strong assumptions. This paper discusses identification and estimation of natural direct...

Based on new, exceptionally informative and large German linked employer-employee administrative data, we investigate the question whether the omission of important control variables in matching estimation leads to biased impact estimates of typical active labour market programs for the...