A Job Ladder Model of Firm, Worker, and Earnings Dynamics

This paper proposes a multiworker firm model with on-the-job search and decreasing returns-to-scale production. A coalition bargaining solution between a firm and its incumbent workers yields tractability, results in privately efficient recruiting decisions, and delivers an explicit expression for the wage function. The paper shows how a stylized calibrated version of the model can replicate untargeted empirical facts on the cross-sectional dispersion in firm growth and on measured elasticities of separation rates, quitting rates and vacancy duration with respect to wages. It can also replicate observed net poaching rates by firm size and firm wage, therefore rationalizing the absence of firm size ladders and the presence of wage ladders. In terms of business cycles, the model can replicate the cyclical properties of job flows and worker flows