We investigate the role of search frictions in markets with price competition and how it leads to sorting of heterogeneous agents. There are two aspects of value creation: the match value when two agents actually trade and the probability of trading governed by the search technology. We show that positive assortative matching obtains when complementarities in the former outweigh complementarities in the latter. This happens if and only if the match-value function is root-supermodular, that is, its nth root is supermodular, where n reflects the elasticity of substitution of the search technology. This condition is weaker than the condition required for positive assortative matching in markets with random search. Keywords: Competitive search equilibrium, directed search, two-sided matching, decentralized price competition, complementarity, root-supermodularity, sorting
Sorting and Decentralized Price Competition
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.
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
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
International Economic Review, 2011, 52(1), pp 85-104. With M. Galenianos and G. Virag. [technical appendix] In directed search with a finite population, minimum wages improve employment but reduce output and efficiency, and reverse for unemployment benefits. 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
Review of Economic Studies, 2019 86(4): 1411-1447. With Michèle Belot and Paul Muller. We develop and evaluate experimentally a novel tool that redesigns the job search process by providing tailored online advice about related occupations. 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
International Economic Review, 2012, Vol 53 (1), 1-21. With M. Galenianos. We study a finite directed-search wage posting game among heterogeneous firms (allowing for risk aversion, moral hazard,…), including limit theorems. Go to paper