David Card, Joshua Angrist and Guido Imbens Win Nobel in Economics 2021

David Neumark, an economist at the University of California, Irvine, who co-wrote a paper contesting Mr. Card and Mr. Krueger’s findings in the minimum wage study, said he still thought the work had data issues — but added that there was no doubt that the methodology was important.

“They’ve all done great work — they’ve changed the way that labor economists do research,” Mr. Neumark said of the three winners.

Mr. Angrist and Mr. Krueger tried in the early 1990s to gauge how much benefit people derive from extra years of education. To figure it out, they took advantage of the fact that students born earlier in the year can legally leave school earlier than those born later in the year. Those born earlier tended to get less education and also earned less later on. The effect of an additional year of education, they estimated, was a 9 percent increase in income.

That study helped spur the additional work on research methods that Mr. Angrist and Mr. Imbens later carried out. That contribution has reshaped the way researchers think about and analyze natural experiments, according to the Nobel committee.

The pair showed that it was possible to identify a clear effect from an intervention in people’s behavior — like a subsidy that might encourage people to ride bicycles to work — even if a researcher could not control who took part in the experiment, and even if the impact varied across individuals. They also came up with a transparent framework for such research that has increased trust in it.

“The challenge, for me, has always been trying to understand, when people do empirical work, what exactly the methodological challenges are,” Mr. Imbens said via telephone in a news conference for the announcement.

Two American economists affiliated with Stanford, Paul R. Milgrom and Robert B. Wilson, won the 2020 Nobel in economics for improvements to auction theory. Abhijit Banerjee and Esther Duflo of M.I.T. and Michael Kremer of Harvard University won in 2019 for their experiment-based research in development economics.

Article source: https://www.nytimes.com/2021/10/11/business/nobel-economics-prize-david-card-joshua-angrist-guido-imbens.html