arXiv subjects

Tayfun Sönmez

Publications and source records attributed to Tayfun Sönmez.

6 recordsLinked to original sources

arXiv2025

Minimalist Market Design: A Framework for Economists with Policy Aspirations

Minimalist market design is an economic design framework developed from the perspective of an outsider -- one seeking to improve real institutions without a commission or official mandate. It offers a structured, "minimally invasive" method for reforming institutions from within: identify their mission as understood by stakeholders, diagnose the root causes of failure, and refine only those elements that compromise that mission. By fixing what is broken and leaving the rest intact, the framework respects the tacit knowledge embedded in long-standing institutions, minimizes unintended consequences, and secures legitimacy that facilitates adoption. Such targeted interventions often call for novel, use-inspired theory tailored to the institutional context. In this way, minimalist market design advances both theory and practice through a reciprocal process fostering collaboration across disciplines and between academic research and real-world practice. Tracing the framework's evolution over twenty-five years of intertwined progress in theory and real-world implementation across a range of matching market applications -- including housing allocation, school choice, living-donor organ exchange for kidney and liver, military branch assignment in the U.S. Army, the allocation of vaccines and therapies during the COVID-19 pandemic, and the allocation of public jobs and college seats under India's reservation system -- this monograph reveals a consistent "less is more" ethos, showing how restrained, precisely targeted reforms can yield substantial policy improvements while advancing fundamental knowledge.

econ.GN↗

arXiv2024

Informed Neutrality in Minimalist Market Design: A Case Study on a Constitutional Crisis in India

In a 3-2 split verdict, the Supreme Court approved the exclusion of India's socially and economically backward classes from its affirmative action measures to address economic deprivation. Dissenting justices, including the Chief Justice of India, protested the Majority Opinion for sanctioning "an avowedly exclusionary and discriminatory principle." To justify their controversial decision, the majority justices relied on technical arguments that are categorically false. The confusion of the justices is due to a subtle technical aspect of the affirmative action system in India: the significance of overlaps between members of protected groups. Conventionally, protected classes were determined by the caste system, which meant they did not overlap. The addition of a new protected class defined by economic criteria alters this structure, unless it is artificially enforced. The majority justices failed to appreciate the significance of this critical change and inaccurately argued that the controversial exclusion is a technical necessity to provide benefits to previously unprotected members of a new class. We show that this case could have been resolved with three competing policies that each avoid the controversial exclusion. One of these policies aligns with the core arguments in the Majority Opinion, whereas a second aligns with those in the Dissenting Opinion.

econ.GN↗

arXiv2023

Fair Allocation of Vaccines, Ventilators and Antiviral Treatments: Leaving No Ethical Value Behind in Health Care Rationing

A priority system has traditionally been the protocol of choice for the allocation of scarce life-saving resources during public health emergencies. Covid-19 revealed the limitations of this allocation rule. Many argue that priority systems abandon ethical values such as equity by discriminating against disadvantaged communities. We show that a restrictive feature of the traditional priority system largely drives these limitations. Following minimalist market design, an institution design paradigm that integrates research and policy efforts, we formulate pandemic allocation of scarce life-saving resources as a new application of market design. Interfering only with the restrictive feature of the priority system to address its shortcomings, we formulate a reserve system as an alternative allocation rule. Our theoretical analysis develops a general theory of reserve design. We relate our analysis to debates during Covid-19 and describe the impact of our paper on policy and practice.

econ.TH↗

arXiv2023

Redesigning the US Army's Branching Process: A Case Study in Minimalist Market Design

We present the proof-of-concept for minimalist market design (Sönmez, 2023) as an effective methodology to enhance an institution based on the desiderata of stakeholders with minimal interference. Four objectives-respecting merit, increasing retention, aligning talent, and enhancing trust-guided reforms to US Army's centralized branching process of cadets to military specialties since 2006. USMA's mechanism for the Class of 2020 exacerbated challenges implementing these objectives. Formulating the Army's desiderata as rigorous axioms, we analyze their implications. Under our minimalist approach to institution redesign, the Army's objectives uniquely identify a branching mechanism. Our design is now adopted at USMA and ROTC.

econ.TH↗

arXiv2021

Can Economic Theory Be Informative for the Judiciary? Affirmative Action in India via Vertical and Horizontal Reservations

Sanctioned by its constitution, India is home to the world's most comprehensive affirmative action program, where historically discriminated groups are protected with vertical reservations implemented as "set asides," and other disadvantaged groups are protected with horizontal reservations implemented as "minimum guarantees." A mechanism mandated by the Supreme Court in 1995 suffers from important anomalies, triggering countless litigations in India. Foretelling a recent reform correcting the flawed mechanism, we propose the 2SMG mechanism that resolves all anomalies, and characterize it with desiderata reflecting laws of India. Subsequently rediscovered with a high court judgment and enforced in Gujarat, 2SMG is also endorsed by Saurav Yadav v. State of UP (2020), in a Supreme Court ruling that rescinded the flawed mechanism. While not explicitly enforced, 2SMG is indirectly enforced for an important subclass of applications in India, because no other mechanism satisfies the new mandates of the Supreme Court.

econ.TH↗

arXiv2020

Do Black and Indigenous Communities Receive their Fair Share of Vaccines Under the 2018 CDC Guidelines

A major focus of debate about rationing guidelines for COVID-19 vaccines is whether and how to prioritize access for minority populations that have been particularly affected by the pandemic, and been the subject of historical and structural disadvantage, particularly Black and Indigenous individuals. We simulate the 2018 CDC Vaccine Allocation guidelines using data from the American Community Survey under different assumptions on total vaccine supply. Black and Indigenous individuals combined receive a higher share of vaccines compared to their population share for all assumptions on total vaccine supply. However, their vaccine share under the 2018 CDC guidelines is considerably lower than their share of COVID-19 deaths and age-adjusted deaths. We then simulate one method to incorporate disadvantage in vaccine allocation via a reserve system. In a reserve system, units are placed into categories and units reserved for a category give preferential treatment to individuals from that category. Using the Area Deprivation Index (ADI) as a proxy for disadvantage, we show that a 40% high-ADI reserve increases the number of vaccines allocated to Black or Indigenous individuals, with a share that approaches their COVID-19 death share when there are about 75 million units. Our findings illustrate that whether an allocation is equitable depends crucially on the benchmark and highlight the importance of considering the expected distribution of outcomes from implementing vaccine allocation guidelines.

econ.GN↗