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...

To generate big responses of unemployment to productivity changes, researchers have reconfigured matching models in various ways: by elevating the utility of leisure, by making wages sticky, by assuming alternating-offer wage bargaining, by introducing costly acquisition of credit, or by...

We propose a theory of low-frequency movements in unemployment based on asymmetric real wage rigidities. The theory generates two main predictions: long-run unemployment increases with (i) a fall in long-run productivity growth and (ii) a rise in the variance of productivity growth. Evidence...