This chapter assesses how models with search frictions have shaped our understanding of aggregate labor market outcomes in two contexts: business cycle fluctuations and long-run (trend) changes. We first consolidate data on aggregate labor market outcomes for a large set of OECD countries. We...

We extend the concept of competitive search equilibrium to environments with private information, and in particular adverse selection. Principals (e.g. employers or agents who want to buy assets) post contracts, which we model as revelation mechanisms. Agents (e.g. workers, or asset holders)...

This paper extends Lucas and Prescott's (1974) search model to develop a notion of rest unemployment. The economy consists of a continuum of labor markets, each of which produces a heterogeneous good. There is a constant returns to scale production technology in each labor market, but labor...

This paper uses readily accessible data to measure the probability that an employed worker becomes unemployed and the probability that an unemployed worker finds a job, the ins and outs of unemployment. Since 1948, the job finding probability has accounted for three-quarters of the fluctuations...

This paper argues that unemployment insurance increases labor productivity by encouraging workers to seek higher productivity jobs, and by encouraging firms to create those jobs. We use a quantitative general equilibrium model to investigate whether this effect is comparable in magnitude to the...

This paper estimates the response of the unemployment rate and labor force participation rate to exogenous variation in the youth share of the working age population, using cross-state variation in lagged birth rates as an instrumental variable. A one percent increase in the youth share reduces...

This paper studies the assignment of heterogeneous workers to heterogeneous jobs in the presence of coordination frictions. Firms offer human-capital-contingent wages, workers observe these and apply for a job. In a symmetric equilibrium, identical workers use identical mixed strategies in...

The standard theory of equilibrium unemployment, the Mortensen-Pissarides search and matching model, cannot explain the magnitude of the business cycle fluctuations in two of its central elements, unemployment and vacancies. Modifying the model to make the present value of wages unresponsive to...

This paper develops a dynamic model of mismatch. Workers and jobs are randomly assigned to labor markets. Each labor market clears at each instant but some labor markets have more workers than jobs, hence unemployment, and some have more jobs than workers, hence vacancies. As workers and jobs...