On-the-job search and cyclical unemployment: Crowding out vs. vacancy effects

Incorporating on-the-job search (OTJS) into a real business cycle model has been shown to increase the cyclical volatility of unemployment. Using a particularly simple model of OTJS, we show that the increased search of employed workers during expansions induces firms to open more vacancies, but also crowds out unemployed workers in the job search, resulting in an ambiguous overall effect on unemployment volatility. We show analytically and numerically that the difference between the employer׳s share of the match surplus with an employed versus an unemployed job seeker determines the degree to which OTJS increases unemployment volatility. We use this result to re-consider some related papers of OTJS and explain the amplification of volatility they obtain. Finally, we show that a plausible calibration of the OTJS model allows us to reproduce most significant features of the US labor data.