Estimation of a Roy/Search/Compensating Differential Model of the Labor Market

In this paper, we develop a model that captures key components of the Roy model, a search model, compensating differentials, and human capital accumulation on-the-job. We establish which components of the model can be non-parametrically identified and which ones cannot. We estimate the model and use it to assess the relative contribution of the different factors for overall wage inequality. We find that variation in premarket skills (the key feature of the Roy model) is the most important component to account for the majority of wage variation. We also demonstrate that there is substantial interaction between the other components, most notably, that the importance of the job match obtained by search frictions varies from around 4% to around 29%, depending on how we account for other components. Inequality due to preferences for non-pecuniary aspects of the job (which leads to compensating differentials) and search are both very important for explaining other features of the data. Search is important for turnover, but so are preferences for non-pecuniary aspects of jobs as one-third of all choices between two jobs would have resulted in a different outcome if the worker only cared about wages.