The term was coined in 1952 by William H. Whyte Jr.. Most of the initial research on groupthink was conducted by Irving Janis, a research psychologist from Yale University. Janis published an influential book in 1972, which was revised in 1982. Janis used the Bay of Pigs disaster (the failed invasion of Castro's Cuba in 1961) and the Japanese attack on Pearl Harbor in 1941 as his two prime case studies. Later studies have evaluated and reformulated his groupthink model.