MIT economics professor; co-founder and director, Abdul Latif Jameel Poverty Action Lab (JPAL)
Rank change: New
Duflo, a French development economist, is a champion of randomized field experiments to test how well poverty-fighting programs are working. She helped launch JPAL, which measures things like whether reducing class size helps kids learn better in Kenya (it doesn't) or whether having teachers photograph themselves at school every day reduces teacher absenteeism in India (it does). Duflo won a MacArthur grant in 2009 and this year was awarded the John Bates Clark Medal, often a precursor to a Nobel Prize.
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Last updated October 14 2010: 1:25 PM ET