Mortensen, Dale Thomas, 1939–2014, American economist, b. Enterprise, Oreg., Ph.D. Carnegie-Mellon Univ., 1967. Mortensen a professor at Northwestern Univ. for his entire academic career. His work focused on the labor market, exploring the so-called friction involved in job search, labor turnover, and the like and developing techniques for studying and understanding the labor market and the effects that government policies have on them. Along with Peter Diamond and Christopher Pissarides, he developed matching theory and the Diamond-Mortensen-Pissarides model, and for this work the three were awarded the Nobel Memorial Prize in Economic Sciences in 2010. Mortensen also used his insights to examine the "marriage market," the process in which individual finds a spouse or partner. Among his works is Wage Dispersion: Why Are Similar Workers Paid Differently? (2005).