YCMS Tsinghua; Senior Research Fellow at Fox / Temple U, Emeritus at Harvard U

University of Chicago

University of Chicago

Harvard University

Professor and Director, Institute for Population Heath, King's College London

Mathematics, IBM/Yale University

professor of economics,harvard university

Professor of Mathematics, Princeton University

Massachusetts Institute of Technology

LSE (1931-1950), University of Chicago (1950-62), University of Freiburg (1962–68)