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Monday, 11 May, 2026
Sona Badalyan: Essays in Personnel Economics: Aging Workforce and Worker Substitutability
Dissertation Committee:
Štěpán Jurajda (CERGE-EI, chair)
Wolfgang Dauth (Otto Friedrich University in Bamberg, IAB)
Randall Filer (City University of New York)
Paolo Zacchia (Ca’ Foscari University of Venice, CERGE-EI)
Defense Committee:
Nikolas Mittag (CERGE-EI, chair)
Teresa Freitas-Monteiro (CERGE-EI)
Kamil Galuščák (Research Institute for Labor and Social Affairs (RILSA))
Referees:
Simon Jäger (Princeton University)
Johannes Geyer (DIW Berlin – German Institute for Economic Research)
Meeting link: https://cerge-ei.webex.com/cerge-ei/j.php?MTID=mc71c48cdf3f73bef8c2a5a02506f79a4
Meeting number: 2740 133 9332
Meeting password: 366548
Abstract:
This dissertation studies how retirement age reforms reshape labor markets beyond individual retirement decisions, focusing on firms, coworkers, and workplace interactions. Using quasiexperimental evidence from German pension reforms that raised women’s early retirement age, I examine how delayed retirements affect internal labor markets, worker substitutability, and peer behavior at older ages. The first chapter shows that retaining older workers generates substantial intra-firm spillovers. Delayed retirements reduce internal promotions and external hiring of younger coworkers, with the largest losses among middle-aged workers closest to older workers on career ladders. These effects are highly structured: promotion crowd-out arises in dense internal labor markets with intense competition and operates primarily within jobcells, while coworkers in other jobcells can benefit when retained older workers possess firm-specific human capital. Hiring declines, by contrast, are concentrated in thin external labor markets where replacement is difficult, highlighting that without accounting for hiring frictions, crowd-out effects cannot be interpreted as pure measures of worker substitutability. The second chapter demonstrates that retirement age reforms help firms retain less substitutable workers with job-specific skills and managerial responsibilities, preserving valuable human capital that would otherwise be lost through voluntary exits. The third chapter shows that reform effects are further amplified through peer behavior: women are more likely to remain employed at older ages when their coworkers do so, explained by conformity, information, and work complementarity mechanisms. Together, these chapters show the interdependence of coworker careers through slot constraints, human capital, and social interactions.
Full Text: "Essays in Personnel Economics: Aging Workforce and Worker Substitutability"
