David Card, Joshua D. Angrist and Guido W. Imbens have made a career of studying unintended experiments — Mr. Card in labor economics and Mr. Angrist and Mr. Imbens in analyzing cause and effect.
All three winners are based in the United States. Mr. Card, who was born in Canada, works at the University of California, Berkeley. Mr. Angrist, born in the United States, is at M.I.T. and Mr. Imbens, born in the Netherlands, is at Stanford University.
“Uncovering causal relationships is a major challenge,” said Peter Fredriksson, chairman of the prize committee. “Sometimes, nature, or policy changes, provide situations that resemble randomized experiments. This year’s laureates have shown that such natural experiments help answer important questions for society.”
Mr. Card’s work has challenged conventional wisdom in labor economics — including the idea that higher minimum wages led to lower employment. He was a co-author of influential studies on that topic with Alan B. Krueger, who died in 2019, including one that used the natural geographical border between New Jersey and Pennsylvania to test the effect of a minimum wage change. Comparing outcomes between the states, the research found that employment at fast food restaurants was not affected by an increase in New Jersey’s minimum wage.
Mr. Angrist and Mr. Imbens have contributed to the way researchers think about and analyze natural experiments.
They showed that it is 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 cannot control who takes part in the experiment, and even if the impact varies across individuals. The pair also came up with a transparent framework for such research that has increased trust in it. …
Nobel in economics goes to David Card, Joshua Angrist and Guido Imbens
NY Times – October 11