John Harsanyi

Bayesian games; types.

Hungarian-American economist and professor at the University of California, Berkeley, awarded the Nobel Memorial Prize in Economic Sciences in 1994 alongside John Nash and Reinhard Selten. His landmark contribution was transforming games of incomplete information into tractable Bayesian games by modelling each player's private information as a randomly drawn 'type' from a common prior distribution. This Harsanyi transformation became the standard foundation for auction theory, mechanism design, and signalling models.