Klein, Lawrence Robert, 1920-, American economist, b. Omaha, Nebr. He has been active in academia, government, and private research institutes throughout the world since the 1940s. Klein's 1947 book The Keynesian Revolution established him as one of the foremost scholars on Keynesian economics. His influential studies in econometrics brought him further recognition, particularly his book An Econometric Model of the United States, 1929-52 (1955, repr. 1966). In 1980 he was awarded the Nobel Memorial Prize in Economic Sciences.