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

Abstract

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.

Non-Standard Choice in Matching Markets

“…For instance, in school admissions, parents report challenges in navigating choice. 18 In the US Army's branching system, ranking both branch assignment and length of service commitment jointly is considered complex (see Greenberg et al (2021)). Moreover, in practice, individuals have often been found to make mistakes that strategic considerations cannot explain (see, e.g., Narita (2018) and Shorrer and Sóvágó (2018)).…”

“…Ranking both branch assignment and length of service commitment jointly is considered too complex (see Greenberg et al (2021)). In general, when potential assignments have multiple attributes considerations about the complexity of choice cannot be kept aside.…”

“…5 Multi-attribute assignments are commonplace in real-life matching problems. For example, assignments in the US Army's branching system consist of branch assignment and length of service (Sönmez and Switzer (2013), Sönmez (2013), Greenberg et al (2021)). Assignments in centralized college admissions markets (e.g., that of the University of Delhi) consist of college-course pairs.…”

Efficient and Strategy-Proof Cardinal Rules on a Restricted Domain

“…Sönmez (2023) elaborates a market design paradigm called minimalist market design. Greenberg, Pathak, and Sönmez (2023) provide a priority design for the branching of the US Army from this perspective.…”