Prof. Howard Rosenthal, a political scientist whose pioneering research confirmed quantitatively that Congress is more politically polarized than at any point since Reconstruction, died on July 28 at his home in San Francisco. He was 83.

“Professor Rosenthal was a trailblazing figure in political science, who collaborated with economists and drew on game theory and other formal methods to help define the modern subfield of political economy,” said Prof. Alan Patten, chairman of the politics department at Princeton, where Professor Rosenthal taught between stints at Carnegie Mellon University in Pittsburgh and New York University. “He was especially known for work measuring and analyzing political polarization, a phenomenon that is of more relevance than ever in contemporary American politics.”

Professor Rosenthal was awarded the Duncan Black Prize from the Public Choice Society in 1980, the C.Q. Press Award from the American Political Science Association in 1985, and the William H. Riker Prize for Political Science from the University of Rochester in 2010.