· Allen and Lenabelle Davis Professor of Economics and Social Sciences, Emeritus, California Institute of Technology1985–
· Sydney G. Harris Professor of Social Science, Northwestern University1983–1985
· Associate Professor, Northwestern University1971–1975
· Assistant Professor, Northwestern University1970–1971
· Assistant Professor, Carnegie Mellon University1967–1970
· Ph.D. in Economics, Purdue University1967–
· M.S. in Economics, Purdue University1965–
· Instructor, Wabash College1965–1966
· A.B. in Mathematics, Wabash College1963–