US Army let a matching algorithm assign officers to branches, not a committee

Every year thousands of new officers are assigned to Army branches — infantry, armor, cyber, and the rest — through a centralized matching process that decides how the Army uses its talent for decades.

The West Point mechanism used for the Class of 2020 made the Army's own policy aims harder to hit: cadets could game their preferences, and the result misaligned talent with the branches that the service most wanted to keep and staff.

Economists modelled it as a market design problem and found the Army's objectives uniquely pin down both which cadet gets which branch and what priority policy to use — a uniqueness result. They redesigned the mechanism and the priority policy together instead of patching one.

The repaired design, built on a cumulative-offer mechanism, was adopted for new classes at both West Point and ROTC, which assign around 70% of newly commissioned officers.