We study a labour market in which firms can observe workers’ output but not their effort, and in which a worker’s productivity in a given firm depends on a worker-firm specific component, unobservable for the firm. Firms offer wage contracts that optimally trade off effort and wage costs. As...

It is well known in personnel economics that firms may improve the quality of their workforce by offering performance pay. We analyse an equilibrium model where worker productivity is private information and show that the gains to the firms from worker self-selection may not be matched by a...