TY - BOOK AU - Azar,José AU - Marinescu,Ioana AU - Steinbaum,Marshall I. ED - National Bureau of Economic Research. TI - Labor Market Concentration T2 - NBER working paper series PY - 2017/// CY - Cambridge, Mass. PB - National Bureau of Economic Research N1 - December 2017; Hardcopy version available to institutional subscribers N2 - 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 CareerBuilder.com, 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 UR - https://www.nber.org/papers/w24147 UR - http://dx.doi.org/10.3386/w24147 ER -