John Duffy (born January 2, 1964) is an American economist. He earned an A.B. in Economics from the University of California, Berkeley and a Ph.D. in Economics from the University of California, Los Angeles. He is currently Professor of economics at the University of Pittsburgh where he serves as Director of the Pittsburgh Experimental Economics, a leading center of experimental economics research. Duffy's research interests are in macroeconomics, experimental economics, and agent-based modelling.