A growing literature on inference in difference-in-differences (DiD) designs with grouped errors has been pessimistic about obtaining hypothesis tests of the correct size, particularly with few groups. We provide Monte Carlo evidence for three points: (i) it is possible to obtain tests of the...

This overview describes the development of methods for empirical research in the field of labor economics during the past four decades. This period is characterized by the use of micro data to answer policy relevant research question. Prominent in the literature is the search for exogenous...

Based on local variations in vocational rehabilitation (VR) priorities, we examine the impacts of alternative VR programs on short- and long-term labor market outcomes for temporary disability insurance (TDI) claimants in Norway. The analysis builds on rich and detailed administrative registers...

In this paper we evaluate the premise from the recent literature on Monte Carlo studies that an empirically motivated simulation exercise is informative about the actual ranking of various estimators when applied to a particular problem. We consider two alternative designs and provide an...

We study semiparametric two-step estimators which have the same structure as parametric doubly robust estimators in their second step, but retain a fully nonparametric specification in the first step. Such estimators exist in many economic applications, including a wide range of missing data and...

In this paper, we assess the impact of firms introducing part-time work schemes for gradual labour market exit of elderly workers on their employees' labour market outcomes. The analysis is based on unique linked employer-employee data that combine high-quality survey and administrative data....

This paper discusses the nonparametric identification of causal direct and indirect effects of a binary treatment based on instrumental variables. We identify the indirect effect, which operates through a mediator (i.e. intermediate variable) that is situated on the causal path between the...

We evaluate a comprehensive activation program in Norway targeted at hard-to-employ social assistance claimants with reduced work capacity. The program offers a combination of tailored rehabilitation, training and job practice, and a generous, stable, and non-means-tested benefit. Its main aims...

This paper investigates the finite sample performance of a comprehensive set of semi- and nonparametric estimators for treatment and policy evaluation. In contrast to previous simulation studies which mostly considered semiparametric approaches relying on parametric propensity score estimation,...

This study is an empirical assessment of the impact of the drug decriminalization policy followed by Portugal in July, 2001. We investigate especially the impact of the policy change on the price of illicit drugs. The analysis is performed using a difference-in-differences approach and a...