Dale T. Mortensen passed away on January 9, 2014.

He was Professor of Economics and Director of the Mathematical Methods in the Social Sciences Program at Northwestern University. His research and teaching interests are in labor economics, macroeconomics and economic theory.

Professor Mortensen received his B.A. in Economics from Willamette University and his Ph.D. in Economics from Carnegie-Mellon University. A faculty member of Northwestern University since 1965, he also held visiting appointments at the University of Essex, Hebrew University, New York University, California Institute of Technology, and Cornell University as well as visiting research appointments at the Central Institute of Mathematics-Economics in Moscow, Russia, the Centre for Labor and Social Research in Aarhus, Denmark, and the Research School of Social Sciences at Australian National University.

Mortensen pioneered the theory of job search and search unemployment and extended this to study labor turnover, research and development, personal relationships, and labor reallocation. His insight that friction is equivalent to the random arrival of trading partners has become the leading technique for analysis of labor markets and the effects of labor market policy. The development of equilibrium dynamic models designed to account for wage dispersion and the time series behavior of job and worker flows are the principal topics of his latest research. His publications include over fifty scientific articles and contribution to books. His most recent book, Wage Dispersion: Why Are Similar Workers Paid Differently, was published by MIT Press in 2003.

Mortensen was president of the Society of Economics Dynamics, one of the founding editors of the Review of Economic Dynamics, a Fellow of the Econometric Society, and a Fellow of the American Academy of Arts and Sciences.

Dale Mortensen joined IZA as a Research Fellow in November 2001. He received the 2005 IZA Prize in Labor Economics and the 2010 Nobel Prize for Economic Sciences.

He will be deeply missed.