Jonathan Herbert Schaeffer (born 1957) is a Canadian researcher and professor at the University of Alberta and the Canada Research Chair in Artificial Intelligence.
Born in Toronto, Ontario, he received a Bachelor of Science degree in 1979 from the University of Toronto. He received a Master of Mathematics degree in 1980 and a Ph.D. in 1986 from the University of Waterloo. Schaeffer reached national master strength in chess while in his early 20s, but has played little competitive chess since that time.
Chinook is the first computer program to win the world champion title in a competition against humans. In 1990 it won the right to play in the human World Championship by being second to Marion Tinsley in the US Nationals. At first the American Checkers Federation and English Draughts Association were against the participation of a computer in a human championship. When Tinsley resigned his title in protest, the ACF and EDA created the new title Man vs. Machine World Championship, and competition proceeded. Tinsley won with four wins to Chinook's two.
In a rematch, Chinook was declared the Man-Machine World Champion in checkers in 1994 in a match against Marion Tinsley after six drawn games, and Tinsley's withdrawal due to pancreatic cancer. While Chinook became the world champion, it had never defeated the best checkers player of all time, Tinsley, who was significantly superior to even his closest peer.
The championship continued with Chinook defending its title against Don Lafferty when it lost one game, won one and drew 18. After the match, Jonathan Schaeffer decided not to let Chinook compete anymore, but instead try to solve checkers. It was rated at 2814.
In 2007, after 18 years of computation, he proved through a weak solution that checkers always results in a draw if neither player makes a mistake. The solution involved 1014 calculations from an initial position of 10 pieces on the board.
Currently Dr. Schaeffer is the Vice-Provost for Information Technology at the University of Alberta.
- Schaeffer, Jonathan. One Jump Ahead:: Challenging Human Supremacy in Checkers, 1997, Springer, ISBN 978-0387949307.
- Solving Checkers by J. Schaeffer, Y. Björnsson, N. Burch, A. Kishimoto, M. Müller, R. Lake, P. Lu and S. Sutphen
- Partial Information Endgame Databases by Yngvi Björnsson, Jonathan Schaeffer, and Nathan R. Sturtevant