There is no robust empirical support for the effect of financial incentives on the decision to work in self-employment rather than as a wage earner. In the literature, this is seen as a puzzle. We offer a focus on the opportunity cost, i.e. the wages given up as an employee. Information on...

We extend the Altonji and Card (1991) framework for analysing the impact of immigrants on natives' wages from two to three labour types and estimate reduced form wage equations for The Netherlands, United Kingdom and Norway. We find very small effects on natives' wages and no dominant robust...