Viva!  Wbridge5...repeating as ‘robotic’ world champion

Al Levy

Along with over 7,500 humans, there were 7 bridge ‘robots’ playing bridge at the Las Vegas NABC. For those not familiar, a bridge robot is a bridge-playing computer program. While the humans were competing for masterpoints and North American titles, the robots were vying for the title of world computer-bridge champion. At the suggestion of the late Alan Truscott, and at my request, the ACBL established the World Computer-Bridge Championship in 1996, and with the added support and recognition of the World Bridge Federation, this championship has been run annually ever since. These championships are meant to publicize our game, promote the development of bridge software, highlight robotic play, add another dimension to bridge players' experiences and crown an annual champion.

Seven software developers from around the world brought their robots to compete in the main event, a 32-board round robin team event with the top four teams, a team consisting of four identical robots, advancing to the 64-board KO stage. The top four qualifiers were Jack, The Netherlands (155 out of a possible 165 VPs), Shark Bridge, Denmark (123), Wbridge5, France (116) and Micro Bridge, Japan (110). Out of the money were Q-Plus Bridge, Germany (91), Bridge Baron, USA (85) and RoboBridge, The Netherlands (48). In the semifinals, Jack defeated Micro Bridge, 166-112, and Wbridge5 narrowly beat Shark Bridge, 139-121. After five-days and 320 boards, Wbridge5 repeated as champion, defeating Jack in the final KO, 172-157.

Dealer South. Vulnerable N-S.
	♠ A 7 4 ♥ A 9 5 ♦ A K Q 3 ♣ Q 9 6
♠ Q 5 ♥ 6 ♦ J 9 8 6 5 ♣ J 8 7 5 2		♠ J 9 6 3 2 ♥ Q J 8 ♦ 10 2 ♣ K 4 3
	♠ K 10 8 ♥ K 10 7 4 3 2 ♦ 7 4 ♣ A 10

Against 6♥ by Wbridge5, Shark Bridge led the ♠Q. If trumps are 2-2, the slam is cold and if there is a trump loser, then there are squeeze possibilities with threats in the other three suits. A human knows that it may have to ‘best’ guess which distributions to play for, so does Wbridge5.

Wbridge5 won the ♠K in hand. A double dummy simulation determined that the contract could be made more often by winning the king in hand than by winning the ace in dummy.  A heart was played to the ace and a heart returned to the jack and 3 — Wbridge5 ducked the heart!  A simulation, at this point, determined that the contract could always be made if hearts are 2-2, and could be made more often by ducking than by winning the king when trumps are 3-1.

East returned the ♦10. Now it was up to Wbridge5 to determine the actual holdings. Declarer won the ♦A in dummy, led a heart to the king and ran hearts coming down to the following position.

On the ♥4, West discards the ♠5 and Wbridge5 must now determine the remaining distribution. Wbridge5 gets it right by discarding the ♠7 from dummy. Now a spade to dummy's ace squeezed West. West blanked the ♣J, by force. Then the ♦K and ♦Q squeezed East into keeping the ♠J and the lone ♣K and declarer pitched the ♠10. Wbridge5 now won the last two club tricks for 1430.

Near the end of the final KO, there was a 25-hcp grand slam. While Wbridge5 did well to reach 6♦, Jack did even better, reaching the lay-down grand using a system perfect for these hands.

⁽¹⁾ one or four key cards

⁽¹⁾ Strong one-suiter.
⁽²⁾ Positive, less than 2 spades, 3+ length in the other suits.
⁽³⁾ Agreed diamonds as trump, 10-12 support points.
⁴⁾ One or four key cards.
⁽⁵⁾ Do you have the trump queen?
⁽⁶⁾ No.
⁽⁷⁾ I really didn't need the trump queen as partner has 3+ trumps, at most one spade and the heart ace.

Jack found the lay-down grand, while Wbridge5 didn't explore further over 5♦. 11 Imps to Jack.

For all this year's results, the history and results of all past championships and information on the contestants go to www.computerbridge.com