Essays on Models of the Labour Market with On-the-Job Search

Change log
Gottfries, Axel 

In my first chapter, I provide a solution for how to model bargaining when there is on-the-job search and worker turnover depends on the wage. Bargaining is a standard feature in models without on-the-jobs search, but, due to endogeneity of the match surplus, a solution does not exist when worker turnover depends on the wage. My solution is based on wages being infrequently renegotiated. With renegotiation, the equilibrium wage distribution and the bargaining outcomes are both unique and the model nests earlier models in the literature as limit cases when wages are either continuously or never renegotiated. Furthermore, the rate of renegotiation has important implications for the nature of the equilibrium. A higher rate of renegotiation lowers the response of the match duration to a wage increase, which decreases a firm's willingness to accept a higher wage. This results in a lower share of the match surplus going to the worker. Moreover, a high rate of renegotiation also lowers the positive wage spillovers from a minimum wage increase, since these spillovers rely on firms' incentives to use higher wages to reduce turnover.

In the standard job ladder model, search is modelled via an employment-specific Poisson rate. The size of the Poisson rate governs the size of the search friction. The Poisson rate can represent the frequency of applications by workers or the rate at which firms post suitable vacancies. In the second chapter, which is co-authored with Jake Bradley, we set up a model which has both of these aspects. Firms infrequently post vacancies and workers occasionally apply for these vacancies. The model nests the standard job ladder model and a version of the stock-flow model as special cases while remaining analytically tractable and easy to estimate empirically from standard panel data sets. The structurally estimated parameters are consistent with recent survey evidence of worker behavior. The model fits moments of the data that are inconsistent with the standard job ladder model and in the process reconciles the level of frictional wage dispersion in the data with replacement ratios used in the macro labor literature.

In my third chapter, which is co-authored with Coen Teulings, we develop a simple method to measure the position in the job ladder in models with on-the-job search. The methodology uses two implications from models with on-the-job search: workers gradually select into better paying jobs until they get laid off at which time they start again to climb the job ladder. The measure relies on two sources of variation: (i) time-variation in job-finding rates and (ii) individual variation in the time since the last lay-off. We use the method to quantify the returns to on-the-job search and to establish the shape of the wage offer distribution by means of simple OLS regressions with wages as dependent variables. Moreover, we derive a simple prediction on the distribution of job durations. Applying the method to the NLSY 79, we find strong support for this class of models. We estimate the standard deviation of the wage offer distribution to be 12%. OJS accounts for 30% of the experience profile and 9% of the total wage dispersion.

Teulings, Coen
Erdil, Aytek
on-the-job search, bargaining, wage dispersion, job ladder, stock flow matching
Doctor of Philosophy (PhD)
Awarding Institution
University of Cambridge