Can computers play bridge?

Press, 30 May 1989, Page 13

Can computers play bridge?

CONTRACT BRIDGE

J.R. Wignail

In a flamboyant interview for one of Britain’s Sunday sensationals, Zia Mahmoud offered one million pounds of his own money to anyone who could produce a computer that could beat him at bridge. He had just won a substantial prize in a televised rubber bridge game against some of the best players in the world and was in an ebullient mood. An English expert, Derek Rimington, a computer programmer with vast experience, analysed a few of the deals that was played and came to - the conclusion that Zia " might well have to be very careful. In the match South T dealt this hand with both sides vv'nerable:

- ♦ Q 10 “ Playing with a very ■ good but slightly unfami--2 liar partner, Zia, as South, ‘ arrived in six spades. When the queen of * spades had to make a £ trick, the ace of clubs put « this contract one down. £ Bidding with itself, the 1 computer reached the better spot of six diamonds. * In this contract, South was * able to ruff a spade in the 2 | North hand, so .$■ tricks were easily made.*

The machine bid that one excellently, and on this next hand showed it could defend as well. North dealt with neither side vulnerable:

When West led the two of clubs, an obvious singleton, dummy’s queen was allowed to win the first trick. A low heart was led from the table, East went in with the ace and returned a club for his partner to ruff. Since this was with the king of trumps, the declarer lost only two hearts and a diamond to bring home his doubled game. The computer had no problems. After the same start it played low from the East hand when a trump was led to the second trick. West won with the king, led a diamond to the ace, ruffed the club return with the five of hearts, and later the heart ace defeated the contract by one trick. Perhaps the machine had worked out that West, with no honour cards in diamonds or clubs and with only the spade king, had to have the king of hearts to justify his bidding. The final deal shows it is not too great on declarer play, however. North dealt withVboth sides vulnerable:

The declarer, Tony Forrester, one of the best players in the world, found an excellent way to make 10 tricks. In danger of losing a club, a diamond and two hearts, he ducked the opening lead of the king of clubs, ducked the queen of clubs, and won the third trick with the ace of clubs discarding a diamond from hand. Next he played the ace and king of diamonds, then ruffed a diamond. When the suit divided evenly, it only remained to draw trumps ending on the table and discard a heart on the established six of diamonds. With six tricks in spades, the ace of clubs, and three diamonds South had made his contract. The computer, not surprisingly, failed to rise to

this level of brilliance, but when it was asked to bid the North-South cards it reached a final contract of three no-trumps played by South, and nine tricks were there on top. On this evidence alone, Zia might find it a little more difficult than he thought to win his million pound bet. If he is ever challenged, however, Rimington advises him to take great care. It would be dangerous, for example, to allow a computer to play both the East and West hands, for it might be programmed to peek. Even two separate computers might communicate by laser beam technology, short-wave radio or X-rays. Somehow it seems very unlikely the challenge will ever take place.

The auction was: W N E S — No 1 NT 2V 3V 4? No No Dble All Pass

The auction was: W N E S — No No '14 2V 34* No 44 All Pass