Firms and Labor Market Inequality: Evidence and Some Theory

Working Paper: NBER ID: w22850

Authors: David Card; Ana Rute Cardoso; Jörg Heining; Patrick Kline

Abstract: We survey two growing bodies of research on firm-level drivers of labor market inequality. The first examines how wages are affected by differences in employer productivity. Studies that focus on firm-specific productivity shocks and control for the non-random sorting of workers to firms typically find that a 10% increase in value-added per worker leads to somewhere between a 0.5% and 1.5% increase in wages. Given the wide variation in firm-specific productivity, elasticities of this size suggest that a significant fraction of wage inequality is tied to firm performance. A second literature estimates two-way fixed effects models that rely on the wage changes of people who move between firms to identify firm-specific wage premiums. This literature also concludes that firm pay setting is important for wage inequality, with many studies finding that firm wage effects contribute approximately 20% of the overall variance of wages. To interpret these findings, we develop a model of firm wage setting in which workers have idiosyncratic tastes for different workplaces. We show that simple versions of this model can rationalize the standard two-way fixed effects specification proposed by Abowd, Kramarz and Margolis (1999), and can also match the typical “rent-sharing” elasticities estimated in the literature. Extended versions of the model can potentially explain differences in the wage premiums paid by a given employer to different subgroups of workers.

Keywords: labor market inequality; firm productivity; wage dispersion; rent sharing

JEL Codes: D24; J31; J42


Causal Claims Network Graph

Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.


Causal Claims

CauseEffect
firm productivity (D22)wages (J31)
firm-specific productivity shocks (D22)wages (J31)
firm wage effects (J31)overall wage variance (J31)
higher-ability workers (J24)more productive firms (D21)
sorting of workers to firms (J68)wage inequality (J31)

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