José A. Azar

IESE Business School, Universidad de Navarra
Avinguda Perason 21
08034 Barcelona, Spain

E-Mail: EmailAddress: hidden: you can email any NBER-related person as first underscore last at nber dot org
Institutional Affiliation: IESE Business School

NBER Working Papers and Publications

July 2019Minimum Wage Employment Effects and Labor Market Concentration
with Emiliano Huet-Vaughn, Ioana Marinescu, Bledi Taska, Till von Wachter: w26101
Why is the employment effect of the minimum wage frequently found to be close to zero? Theory tells us that when wages are below marginal productivity, as with monopsony, employers are able to increase wages without laying off workers, but systematic evidence directly supporting this explanation is lacking. In this paper, we provide empirical support for the monopsony explanation by studying a key low-wage retail sector and using data on labor market concentration that covers the entirety of the United States with fine spatial variation at the occupation-level. We find that more concentrated labor markets – where wages are more likely to be below marginal productivity – experience significantly more positive employment effects from the minimum wage. While increases in the minimum wage are ...
March 2018Concentration in US Labor Markets: Evidence From Online Vacancy Data
with Ioana Marinescu, Marshall I. Steinbaum, Bledi Taska: w24395
Using data on the near-universe of online US job vacancies collected by Burning Glass Technologies in 2016, we calculate labor market concentration using the Herfindahl-Hirschman index (HHI) for each commuting zone by 6-digit SOC occupation. The average market has an HHI of 4,378, or the equivalent of 2.3 recruiting employers. 60% of labor markets are highly concentrated (above 2,500 HHI) according to the DOJ/FTC guidelines. Highly concentrated markets account for 20% of employment. For manufacturing industries, we show that labor market concentration is distinct from product market concentration, and is negatively correlated with wages in each industry’s top occupation.

Published: José Azar & Ioana Marinescu & Marshall Steinbaum & Bledi Taska, 2020. "Concentration in US labor markets: Evidence from online vacancy data," Labour Economics, vol 66.

December 2017Labor Market Concentration
with Ioana Marinescu, Marshall I. Steinbaum: w24147
A product market is concentrated when a few firms dominate the market. Similarly, a labor market is concentrated when a few firms dominate hiring in the market. Using data from the leading employment website, we calculate labor market concentration for over 8,000 geographic-occupational labor markets in the US. Based on the DOJ-FTC horizontal merger guidelines, the average market is highly concentrated. Using a panel IV regression, we show that going from the 25th percentile to the 75th percentile in concentration is associated with a 17% decline in posted wages, suggesting that concentration increases labor market power.
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