I study the effect of fatigue and innate ability on performance in a model with incomplete contracts, lumpy tasks requiring multiple periods of work and stochastic productivity shocks. I find that increasing ability or reducing fatigue does not lead necessarily to more productive efficiency,...

Demographic change will have severe impacts on transport, logistics and traffic corporations and systems in Germany and Europe. The most important professional groupings therein are the different driver professions from road, rail and water to the air transport sector. Therefore this research...