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The application window opens this week for the 50th running of the New York City Marathon. It is the biggest marathon in the world - room for more than 50,000 runners - and yet, last year, they had to turn away more than 100,000 people. So how to decide who gets a spot? Kenny Malone from our Planet Money podcast says this is a classic economics problem.
KENNY MALONE, BYLINE: Check, one, two.
Watching last year's New York Marathon, I was reminded how great it feels to not be running a marathon.
You see a lot of people grimacing, and you can tell they look pretty tired.
There are four main ways into this race, and each has its own idea of what is fair. The first is a lottery - fair because everyone who enters has the same odds. But randomness alone ignores something important - skill.
All right, I'm just past mile 19 now - see if I can spot Kristen.
Separate from the lottery, the marathon saves spots for professionals and really fast amateurs like Kristen Calgaro, who got into the race by running a different marathon in a qualifying time.
Here comes Kristen. Here comes Kristen. Kristen.
KRISTEN CALGARO: Hey. How you doing, Kenny?
MALONE: Good. Keep going. Kristen is in her 20th mile and is running faster than if I were just going out and running one mile.
Now, skill and randomness are reasonable ways to allocate a scarce resource, but they leave some big things out, says Costis Daskalakis, a computer scientist who studies fair division problems at MIT.
COSTIS DASKALAKIS: So you would like to allocate some resource to whoever would value it the most. However, you cannot not just go to people and ask them, hey; how much you value this?, because they may say, oh, I value it infinity.
MALONE: Daskalakis says that society sort of defaults to one main way of letting people show how much they value something - money. You love that painting? Buy it at the auction.
DASKALAKIS: Quote, unquote, "you put your money where your mouth is, or you put your mouth where your money is."
MALONE: I think if you put your mouth where your money is, then that's unsanitary.
MALONE: And there are ways to kind of pay your way into the New York Marathon. You can buy an expensive marathon travel package from overseas or raise a couple thousand bucks for specific charities. But the money method leaves out people who value the marathon a lot but don't have access to a lot of money.
DAWN PAPACENA: All my friends work in social services, which - we do not get paid that much in New York City, FYI.
MALONE: Dawn Papacena is a social worker from Brooklyn and desperately wanted to run her hometown marathon. Money wasn't going to work. The lottery was a long shot. There was fast time qualification.
PAPACENA: Which - ha-ha, no. I am not a three-hour runner.
PAPACENA: I am closer to six-hour runner. Yeah.
MALONE: Which I think is great.
MALONE: But it is not going to get you in the race.
PAPACENA: It's not going to get us in the race.
MALONE: Which brings us to the fourth way into the New York marathon - effort. There are spots set aside for people who go and volunteer at one local race and run nine of them, which is a lot of work.
Do you remember which races you ran?
PAPACENA: Yes. I ran the New York City Half, the Queens 10k, the Bronx Ten Miler, the Staten Island Half, the Brooklyn Half, the Al Gordon...
MALONE: A fair solution to a scarce resource problem may not allow more people to get that scarce thing, but it can make people feel more OK when they get left out. The genius of the New York marathon is that by combining four different fair solutions, it minimizes the room for complaint while still rejecting enough runners to fill a small city.
Kenny Malone, NPR News.
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