Two cornerstones of empirical and policy analysis of firms in industrial organization, macro and labor are the determinants of the firm size distribution, and the determinants of sorting between workers and firms. We propose a unifying theory of production where management resolves a tradeoff between hiring more versus better workers. The span of control or size is therefore intimately intertwined with the sorting pattern. We provide a condition for sorting that captures this tradeoff between the quantity and quality of workers and that generalizes Becker’s sorting condition. A system of differential equations determines the equilibrium allocation, the firm size and wages, and allows us to characterize the allocation of the quality and quantity of labor to firms of different productivity. We show that our model nests a large number of widely used existing models. We also augment the model to incorporate labor market frictions in the presence of sorting with large firms.
Assortative Matching with Large Firms
Econometrica. 2018 86(1): 85-132. With Jan Eeckhout.
When heterogeneous firms can choose both how many and which workers to hire, we illustrate consequences for firm-size and wage inequality.
Note a correction for the condition with capital: corrigendum.
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Review of Economic Studies, 2011, Vol. 78 (3), 872-906. With Jan Eeckhout. Wage and employment data can identify the strength of sorting in search models, though two-sided fixed effects are always mis-specified. Go to paper
Publications
Journal of Economic Literature, 2021 59(1): 90-148. With R. Wright,B. Julien, and V. Guerrieri. This survey presents a comprehensive overview of the directed/competitive search literature. Go to paper
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Inferring Risk Perceptions and Preferences using Choice from Insurance Menus: Theory and Evidence
Economic Journal, 2021 131: 713-744. With Ericson, Spinnewijn &, Starc Demand for insurance can be driven by high risk aversion or high risk, and we show how to separate the two using observed market shares. Go to paper
Journal of Economic Theory, 2010/145, 1354-1385. With Jan Eeckhout. Search affects competing mechanisms: if meetings with low types reduce those of high types, price posting and market separation replace auctions. Go to paper
American Economic Journal - Macroeconomics, 2022, 14(4), 1-97, with Michèle Belot and Paul Muller. In a field experiment, we study how job seekers respond to posted wages by randomly assigning wages randomly to pairs of otherwise similar vacancies in a large number of professions, which generates significantly more but not exclusive interest at higher wages. Go to paper
Econometrica, 2019 87(4): 1081-1113. With J. Greenwood, C. Santos and M. Tertilt A calibrated equilibrium search model of an HIV/AIDS epidemic is developed to analyze the direct impact and the behavioral adjustment to policies. Go to paper
Publications
Econometrica, 2010, Vol. 78(2), 539–574. With Jan Eeckhout. In search models with price competition the sorting of heterogeneous buyers and sellers depends on complementarities both in output and in search. Go to paper
Publications
Journal of the European Economic Association, 2022, 20(6), 2317–2352. This paper showcases studies that illustrate the potential of analyzing online job search data and of intervening in the online job search process, and highlights conditions under which some of the recent interventions are likely to improve market outcomes overall, rather than improving only the outcomes for the treated individuals. Go to paper