Bridge and computers

[Anders Wirgren - Sydsvenska Dagbladet - October 23, 2006]

Can computers play Chess or Bridge? The answer is no, obviously, because no computer can think yet. But if a computer gets good instructions, i.e. a well written program, it can use its enormous calculating power and become skilled at so demanding games as chess and bridge.

The best chess programs have improved very much during recent years, and now they are tough opponents for the very best human players. But the bridge programs aren't so good yet. The main reason is that bridge is a game with incomplete information. In chess you know where the pieces are positioned, but in bridge you don't know which of your opponents who has a missing honor, or how the suits are breaking. Often you have to base your play on probabilities or guesswork. Tactics and psychology are therefore more important in bridge than in chess.

But the bridge programs are also improving. The best of them is called Jack. It is in English, developed by a Dutch team and has won the world championship for computers five times since 2001. The latest victory came in Verona, Italy (June 17-22, 2006), when eight programs competed. Jack won the round robin by a big margin, and the semi final even easier, to face Micro Bridge from Japan in the final. And Jack was superior there too, winning 217-54. One of its many good boards comes here:

West dealer, neither side vulnerable

  -
A Q 10 6 5 4
A K Q 6 3
Q J
A 10 7 4
J 7 3 2
J 10 2
4 2
N
WO
Z
Q J 9 8 3 2
-
8 4
A K 10 8 7
  K 6 5
K 9 8
9 7 5
9 6 5 3

With Jack North-South, North opened with 1 heart. East overcalled 2 hearts (spades and a minor). South doubled to show a raise to 2 hearts. West bid 2 spades. North jumped to 4 diamonds, and East bid 4 spades. South doubled, a doubtful move, which worked very well when North removed to 5 hearts. Three pass followed; +450 to Jack.

At the other table, Micro Bridge's North opened with 2 clubs, artificial and forcing. East overcalled 2 spades, South doubled to show 5 HCP or more, and West preempted with a jump to 4 spades. North showed his longest suit with 5 hearts, but when East had excellent distribution and knew his partner had good spade support, Jack bid 5 spades, doubled by South. The king of spades was onside and East's clubs could be established with one ruff, so 5 spades also made. 15 IMPs to Jack.

Last year Jack played a couple of matches against seven of the best pairs in the Netherlands, and it did a remarably good result. Yes, the humans won by 385-359, but Jack won three of the seven matches and shows that we soon have to take the program seriously. Version 4 will be released in November, and the rumours say it is much better than its predecessor. We'd better watch out!