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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Delegated Social Responsibility: Is Managerial Prosociality a Source of Agency Cost?
Wiebke Szymczak
IWH Discussion Papers,
No. 2,
2026
Abstract
Agency theory holds that managerial discretion over stakeholder decisions creates agency costs through altruistic redistribution. We test this claim in a principalagent experiment where agents choose effort and transfers affecting a third party under unenforceable flat-wage contracts. We find that principals set ethically constrained targets and wages that track fairness benchmarks. Agents, however, do not divert resources to stakeholders: transfers are negative on average, and prosocial traits do not increase giving. Instead, contract terms, though unenforceable, systematically shape effort, transfers, and returns. Notably, prosocial agents generate higher total returns. Prosociality appears to mitigate rather than create efficiency losses, suggesting that discretion channels norm-sensitive loyalty rather than stakeholder redistribution.
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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
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Essays on Firms and Market Performance
Tommaso Bighelli
PhD Thesis, db-thueringen,
2024
Abstract
In Chapter 1, I combine longitudinal administrative firm-level data from Germany with 8,000 local tax changes for identification to show that local tax hikes (cuts) increase (decrease) the local manufacturing share. Firm-level results reveal that this is due to wage, employment, firm entry, and labor productivity in the service sector being more responsive to a tax shock than in manufacturing. With this evidence in mind, I calibrate a two-sector model with heterogeneous firms and profit tax to show that, owing to different structural parameters, a corporate tax cut disproportionately benefits service firms, contributing to the sectoral reallocation from manufacturing to service. In Chapter 2, we derive a European Herfindahl-Hirschman concentration index from 15 micro-aggregated country datasets. We show that European concentration rose due to a reallocation of economic activity towards large and concentrated industries. Over the same period, productivity gains from an increasing allocative efficiency of the European market accounted for 50% of European productivity growth while markups stayed constant. Using country-industry variation, we show that changes in concentration are positively associated with changes in productivity and allocative efficiency. This holds across most sectors and countries and supports the notion that rising concentration in Europe reflects a more efficient market environment rather than weak competition and rising market power. In chapter 3, We study the consequences of the Covid-19 pandemic and related policy support on productivity. We employ an extensive micro-distributed exercise to access otherwise unavailable individual data on firm performance and government subsidies. Our cross-country evidence for five EU countries shows that the pandemic led to a significant short-term decline in aggregate productivity and the direct support to firms had only a limited positive effect on productivity developments.
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East Germany
The Nasty Gap 30 years after unification: Why East Germany is still 20% poorer than the West Dossier In a nutshell The East German economic convergence process is hardly…
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Department Profiles
Research Profiles of the IWH Departments All doctoral students are allocated to one of the four research departments (Financial Markets – Laws, Regulations and Factor Markets –…
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Virtual Conference on Sustainable development, firm performance and competitiveness policies in small open economies
Virtual Conference on Sustainable development, firm performance and competitiveness policies in small open economies This Conference has been jointly organised by CompNet and…
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