This study presents the first empirical test with German establishment level data of a hypothesis derived by Helpman et al. (2004) in a model that explains the decision of heterogeneous firms to serve foreign markets either through exports of foreign direct investment: only the more productive...

This article tests the theory recently put forward by Edward Lazear that individuals with competence in many skills should have a higher probability of being self-employed than others. The empirical results for Germany support this jack-of-all-trades view.