Haavelmo's seminal 1943 paper is the first rigorous treatment of causality. In it, he distinguished the definition of causal parameters from their identification. He showed that causal parameters are de fined using hypothetical models that assign variation to some of the inputs determining...

This study uses panel data describing about 6,500 employees in a large international company to study the incentive effects of performance related pay. The company uses two performance related remuneration mechanisms. One is an individual "surprise" bonus payment. The other is a more structured...

This study utilizes the heterogeneity of the fee abolition for West German secondary schools to identify its effect on enrollment and to obtain an estimate of the price elasticity of demand for education. The analysis is based on administrative school enrollment statistics as well as on...