Assortative Matching between workers and firms provides evidence of the complementarities or substitutes in production. The presence of complementarities is important for policies that aim to achieve the optimal allocation of resources, for example unemployment insurance. We argue that using wage data alone, it is virtually impossible to identify whether Assortative Matching is positive or negative. Even though we cannot identify the sign of the sorting, we can identify the strength, i.e., the magnitude of the cross-partial, and the associated welfare loss. We show first that the wage for a given worker is non-monotonic in the type of his employer. This is due to the fact that in a sorting model, wages reflect the opportunity cost of mismatch. We show analytically that this non-monotonicity prevents standard firm fixed effects to correlate with the true type of the firm. We then propose an alternative procedure that measures the strength of sorting in the presence of search frictions. Knowing the strength of sorting facilitates the measurement of the output loss due to mismatch.
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. Go to paper
Journal of Political Economy, 2017, 124(1), 224-264. With G. Grossman & E. Helpman. (simulations, matlab). We introduce two-sided heterogeneity into a Hecksher-Ohlin-style trade model to study factor reallocation and wage inequality within and across sectors. Go to paper
Journal of Monetary Economics, 2008, Vol. 55, pp. 1054-1066. With M. Galenianos. We characterize price dispersion and welfare in a monetary model with private information: inflation is regressive even though the rich hold more money. Go to paper
B.E. Journals of Theoretical Economics, 2013, Vol 13 (1). With S. Ludwig and A. Sandroni. We document a revealed preference for randomization for “social goods”, while such non-standard behavior is not present for private consumption goods. Go to paper
Econometrica, 2015, Vol 83 (5), 1849-1875. With K. Kim. [online appendix] We introduce cheap-talk into a market game and study if the equilibrium can replicate the constraint efficient allocation under (reserve) price posting. Go to paper
American Economic Review, 2015, Vol 105 (10), 3030-3060. With Leo Kaas. We propose a tractable competitive search model with heterogeneous multi-worker firms, and investigate firm growth and business cycles. Go to paper