Off the Labor Supply Curve: The Zero Employer Size Wage Effect Within Large Firms
André Diegmann, Steffen Müller, Benjamin Schoefer
IWH Discussion Papers,
No. 8,
2026
Abstract
We revisit the employer size wage effect (ESWE) – arguably the most basic and influential departure from the law of one price for labor. Our main result is that this canonical fact disappears completely across establishments within the same firm, even though they operate in different local labor markets. We uncover and dissect this fact by including a firm fixed effect in otherwise standard cross-sectional regressions of wages on establishment size. We implement this demanding specification in population-wide triple-linked firm-establishment-employee data in Germany. This result is new in the ESWE literature (for which our paper also provides the first systematic meta-analysis). This wage-size decoupling is hard to square with the view that employment is determined along a finitely elastic employerspecific labor supply curve – i.e., employers pay exactly the minimum needed for the quantity of labor, but no more – the foundation of the monopsony view. By contrast, large multi-establishment firms (MEF) appear to hire off their labor supply curves (or those curves are very elastic), pay wage premia above the monopsonistic minimum, and leave excess labor supply. We find some evidence for a reemergence of the ESWE within low-premium MEFs. Overall, at least for the 25% of German employment in large firms for which the ESWE disappears, wage setting and employment determination may be better accounted for by alternative models, namely accommodating above-market-clearing wage premia and rationing of labor supply, such as efficiency wage theories.
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Patents, Firm Rents, and Worker Compensation: Causal Evidence from Quasi-random Patent Allocation
Afroza Alam, André Diegmann
IWH Discussion Papers,
No. 6,
2026
Abstract
This paper provides new causal evidence on how patent allowances affect firms and their employees based on quasi-random assignment of patent applications to examiners. Exploiting employer-employee records with newly linked German firm data and web-scraped patent documents, we show that patent-induced shocks reduce firm exit, improve productivity, and increase wages, with rent-sharing elasticities between 0.10 and 0.21. Wage gains are broadly observed across occupational tasks, with high heterogeneity: managers benefit disproportionately in publicly traded firms, whereas broader wage increases accrue to workers in non-traded firms. Our findings highlight the role of institutional features and firm organization in shaping how rents are shared.
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Firm Training, Automation, and Wages: International Worker-Level Evidence
Oliver Falck, Yuchen Guo, Christina Langer, Valentin Lindlacher, Simon Wiederhold
Research Policy,
Vol. 55 (3),
2026
Abstract
Firm training is widely regarded as crucial for protecting workers from automation, yet there is a lack of empirical evidence to support this belief. Using internationally harmonized data from over 90,000 workers across 37 industrialized countries, we construct an individual-level measure of automation risk based on tasks performed at work. Our analysis reveals substantial within-occupation variation in automation risk, overlooked by existing occupation-level measures. To assess whether firm training mitigates automation risk, we exploit within-occupation and within-industry variation. Additionally, we employ entropy balancing to re-weight workers without firm training based on a rich set of background characteristics, including tested numeracy skills as a proxy for unobserved ability. We find that training reduces workers’ automation risk by 3.8 percentage points, equivalent to 8% of the average automation risk. The training-induced reduction in automation risk accounts for 15% of the wage returns to firm training. Firm training is effective in reducing automation risk and increasing wages across nearly all countries, underscoring the external validity of our findings. Training is similarly effective across gender, age, and education groups, suggesting widely shared benefits rather than gains concentrated in specific demographic segments.
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The Geography of Worker-Firm Sorting: Drivers of Rising Colocation
Nils Torben Hollandt, Steffen Müller
IWH Discussion Papers,
No. 22,
2025
Abstract
Spatial segregation of low- and high-wage workers is a persistent economic issue with broad social implications. Using social security data and an AKM wage decomposition, this paper examines spatial wage inequality in West Germany. Spatial inequality in log wages rose sharply between 1998 and 2008, mainly due to increased variance in worker pay premiums across regions (48%) and stronger positive spatial assortative matching of workers and establishments (40%), i.e. colocation. Changes in establishment wage premia are mostly unrelated to rising colocation whereas labor mobility even reduced it. Instead, growth in worker pay premiums among stayers was concentrated in regions where high-wage workers and high-wage establishments were overrepresented already in the 1990s and, thus, magnified pre-existing colocation leading to ‘colocation without relocation’. Germany’s rising trade surplus, especially with Eastern Europe, boosted stayers’ worker pay premiums in those ex-ante high-wage regions and fully explains rising colocation.
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Private Equity in the Hospital Industry
Janet Gao, Yongseok Kim, Merih Sevilir
Journal of Financial Economics,
Vol. 171 (September),
2025
Abstract
We examine the survival prospects, employment profiles, and patient outcomes at private equity (PE)-acquired hospitals. Target hospitals maintain their survival rates while significantly reducing employment and wage expenditures. The number of core medical workers drops temporarily, but returns to its pre-acquisition level in the long run. However, administrative job and wage cuts persist over the long term, particularly at previously nonprofit hospitals. Using proprietary insurance claims data, we find no significant changes in patient demographics or inpatient prices at PE-acquired hospitals. While patient satisfaction declines, there is no evidence of increased patient mortality or readmission rates at PE-acquired hospitals.
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Halle Institute for Economic Research
CALL FOR PAPERS: 21ST IWH/IAB WORKSHOP “TRANSFORMATION PRESSURE IN THE LABOUR MARKET” We welcome contributions on the diverse labour market effects of transformation, adjustment…
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Alumni IWH provides guidance and support in job placement after graduation, including letters of recommendation and career advice. Graduates have found placements in academia…
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Research Clusters
Three Research Clusters Each IWH research group is assigned to a topic-oriented research cluster. The clusters are not separate organisational units, but rather bundle the…
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The Contribution of Employer Changes to Aggregate Wage Mobility
Nils Torben Hollandt, Steffen Müller
Oxford Economic Papers,
Vol. 77 (2),
2025
Abstract
Wage mobility reduces the persistence of wage inequality. We develop a framework to quantify the contribution of employer-to-employer movers to aggregate wage mobility. Using three decades of German social security data, we find that inequality increased while aggregate wage mobility decreased. Employer-to-employer movers exhibit higher wage mobility, mainly due to changes in employer wage premia at job change. The massive structural changes following German unification temporarily led to a high number of movers, which in turn boosted aggregate wage mobility. Wage mobility is much lower at the bottom of the wage distribution, and the decline in aggregate wage mobility since the 1980s is concentrated there. The overall decline can be mostly attributed to a reduction in wage mobility per mover, which is due to a compositional shift toward lower-wage movers.
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Research Articles
Research Articles Explore cutting-edge research based on CompNet’s micro-aggregated firm-level data and related analytical tools. These articles cover empirical and theoretical…
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