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...

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...