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modern · born 1951
Game theory spent decades explaining markets. Alvin Roth started repairing them, redesigning how doctors find hospitals, students find schools, and kidney patients find donors.
Facts reviewed 2026-07-11.
Alvin Roth, a professor at Stanford and before that Harvard, turned the matching theory of Gale and Shapley from an elegant abstraction into working infrastructure. His field, market design, treats a market the way an engineer treats a bridge: as a built object that can fail from congestion, mistrust, or bad incentives, and that can be rebuilt to work.
The markets he works on are the ones without prices. You cannot buy a residency slot, a public school seat, or a kidney; law and ethics forbid it. Somebody still has to decide who gets what, and Roth's insight was that these allocation problems are games whose rules can be redesigned so that honesty is the best strategy and the resulting match is stable.
Roth showed empirically that matching institutions live or die by stability, the property that no doctor and hospital would rather abandon their assigned match for each other. Markets that produced unstable matches unraveled into chaotic early offers; markets built on the stable-matching algorithm survived. He then redesigned the National Resident Matching Program, which places roughly 20,000 doctors a year into United States residency positions [VERIFIED].