Propensity Score Matching (PSM) has become a popular approach to estimate causal treatment effects. It is widely applied when evaluating labour market policies, but empirical examples can be found in very diverse fields of study. Once the researcher has decided to use PSM, he is confronted with...

To tackle mass unemployment and increase participation rates, the German government over recent years has mainly focused on supply side strategies, including 'making work pay' policies. The 2003 Mini-Job reform introduced an extended subsidy of social security contributions for low wage workers....