The 2021 Nobel prize in economics science goes to Imbens, Card and Angrist: what did they discover

Economists David Card, Joshua Angrist and Guido Imbens won the 2021 Nobel economics prize on Monday for pioneering "natural experiments" to show real-world economic impacts in areas from minimum wage increases in the U.S. fast-food sector to migration from Castro-era Cuba. 🏅
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Their research has substantially improved our ability to answer key causal questions. The Nobel committee noted that natural experiments were difficult to interpret, but that Angrist and Imbens had, in the mid-1990s, solved methodological problems to show that precise conclusions about cause and effect could be drawn from them. 🧠
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The prize, formally known as the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel, is the last of this year's crop of Nobels and sees the winners share a sum of 10 million Swedish crowns ($1.14 million). Past Nobel Economics prizes have been dominated by U.S. institutions and this was no exception. 🇺🇸