Counterparties: Economists who did good
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Lloyd Shapley and Alvin Roth have won theÂ Nobel PrizeÂ in economics “for the theory of stable allocations and the practice of market design”. To put it differently, they won the Nobel for their work on “matching markets” through investigations intoÂ marriage, orÂ dwarf tossing,Â orÂ illegal horse meat.
Alex Tabarrok of Marginal RevolutionÂ drillsÂ down into exactly why matching markets matter to our everyday lives: “Matching is a fundamental property of many markets and social institutions. Jobs are matched to workers, husbands to wives, doctors to hospitals, kidneys to patients.”
As Josh GansÂ explainsÂ in the best post on Shapley and Roth’s work, those are markets defined by theirÂ lackÂ of prices. Shapley, a professor emeritus in the economics department at UCLA, is best known for creating, along with D. Gale Johnson, the Gale-Shapley algorithm that creates “stable allocations when two groups of people are to be matched with one another”.
This matching has big impact in the real world: Roth, a Harvard professor who is recently accepted a new position at Stanford, isÂ most heraldedÂ for his development and implementation of Shapley’s theory in kidney donation waiting list policies. Roth’s key insight was figure out a practical way of expanding matching beyond pairs. Here’s Tabarrok again:
Your spouse is dying of kidney disease. You want to give her one of your kidneys but tests show that it is incompatible with her immune system. Utter anguish and frustration. Is there anything that you can do? Today the answer is yes. Transplant centers are now helping to arrange kidney swaps. You give to the spouse of another donor who gives to your spouse. Pareto would be proud. Even a few three-way swaps have been conducted.
But why stop at three? What about an n-way swap?
Catherine Rampell writes in the NYT the answer to this question is also the basis for an algorithm used by “New York, Boston, Chicago and Denver to…Â help assign students to schools”.Â This Forbes profile, and other great background on bothÂ Shapley and Roth (who blogs here), has been culled by Tyler Cowen and Tabarrok atÂ Marginal Revolution. As you read though theÂ quotesÂ of adulation for both men from economists assembled by Mark Thoma, it’s hard to miss the pride they take in work with such clear social benefits. Steven Levitt offers this compliment: “When I talk about economists, one of the greatest compliments I give is to say that they changed the way people think about the world”. –Â Ben Walsh
The joys of refinancing, where “everyday is Groundhog Day” – Chris Taylor
A detailed case against worrying about the housing market -Â Calculated Risk
A bubble we can use: mortgage refinancing – Ben Walsh