Academic Appointment, Affiliation, and Employment History Professor, University of Southern California, 01/01/1996- Associate Professor, University of Southern California, 01/01/1990-01/01/1996 Assistant Professor, University of Southern California, 01/01/1986-01/01/1990 National Science Foundation Post-Doctoral Fellow and Acting Assistant Professor, University of Washington, 01/01/1983-01/01/1986 Member, Mathematical Sciences Research Institute, Berkeley, 01/01/1982-01/01/1983