J. David Singer, RIP

Singer was one of the founding members of the Peace Science Society, an active researcher in conflict resolution, co-creator of the Correlates of War project, and author of several classics in the field of international relations (including "The Level-of-Analysis Problem in International Relations" [pdf]). His views on war and peace, developed during the height of the Cold War, were often controversial; unlike some of his peers he preferred the latter to the former. He encouraged rigorous social scientific analysis, advocated quantitative testing of hypotheses, and built (with others) the most commonly-used data set in conflict research. One bio is here.