Junior (chess)
From Wikipedia, the free encyclopedia
Junior is a computer chess program authored by the Israeli programmers Amir Ban and Shay Bushinsky. Grandmaster Boris Alterman assisted, in particular with the opening book.
Junior won the World Microcomputer Chess Championship in 1997 and 2001 and the World Computer Chess Championship in 2002, 2004, and 2006; both organised by the International Computer Games Association.
In terms of raw power, Junior is dwarfed by other earlier programs such as Deep Blue (which can calculate 200-300 million combinations per second). Deep Junior, which is designed to run on commodity SMP multiprocessor computer hardware, calculates only around 9 million combinations per second, but is more selective about the positions it analyzes.
According to Bushinsky, one of the innovations of Junior over other chess programs is the way it counts moves. Junior counts orthodox, ordinary moves as two moves, while it counts interesting move as only one move, or even less. In this way interesting variations are analyzed more meticulously than less promising lines. This seems to be a generalization of search extensions already used by other programs.
Another approach its designers claim to use is 'opponent modeling'; Junior might play moves that are not objectively the strongest but that play more towards the weaknesses of the opponent.
In 2003 Deep Junior played a 6-game match against Garry Kasparov that resulted in a 3-3 tie. It won a 2006 match with Teimour Radjabov.
Chessbase sells Junior 10 in both single- and multi-processor versions.
