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Computers master the game board

They reign supreme in checkers and chess. Poker may be next. What other areas will artificial intelligence soon dominate?

By Staff writer of The Christian Science Monitor / August 8, 2007

Polaris, a rising star in the poker world, has professional card players fretting. The 16-year-old has a perfect poker face, can shift strategies in an instant, and never gets tired. Well, you do have to recharge the laptop batteries from time to time.

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This crafty computer program is one in a long line of codes designed to compete with humans. And for many games, machines now surpass even the best human opponents. They've dominated chess. They've cracked checkers. And they're homing in on poker.

On July 24, Polaris lost a close match against two top poker players. After two days and 4,000 hands of limit Texas hold em, the computer was behind by only about 30 bets.

"It was a tough opponent," says Ali Eslami, one of the two poker pros who beat Polaris. "To tell you the truth, if I had the chance to face it again right now for money, I wouldn't. There are easier humans out there. I'll stick with them."

The encroachment of lifeless data crunchers into our favorite pastimes marks more than just a countdown until computers are better at virtually everything. Any tabletop defeat is also milestones in the advancement of artificial intelligence.

Sure, checkers and chess players have little hope of even achieving a draw against the best computers. But the more crushing the loss for humans, the more useful the technology is in the real world.

"Games are one of the best ways to test computers and our ability to program them," says Murray Campbell, who worked on the IBM team that created Deep Blue, the first computer to defeat a world chess champion in a six-round match. "As we get better at this kind of artificial intelligence, we'll find more and more applications in other fields – more serious fields: the military, medicine, business."

This ability to flip technology is one Mr. Campbell knows well. His team programmed Deep Blue to master chess through brute force processing. The now retired supercomputer could consider 200 million chess positions a second, mapping out many moves into the future to find the best path to checkmate. (Most human chess players can only handle two or three moves a second, Campbell says. We rely on intuition and other nonquantitative skills.)

Shortly after Deep Blue defeated world champ Garry Kasparov in 1997, IBM integrated the research into corporate and government hardware, Campbell says. IBM borrowed from both the name and architecture of Deep Blue to create the world's most powerful publicly known computer: the Blue Gene/L. Located at the Department of Energy's national laboratory in Livermore, Calif., this powerhouse machine twirls through 280 trillion calculations a second to simulate complex biomolecular processes such as protein folding. In June, IBM beat its own record with a prototype Blue Gene machine capable of 3 quadrillion calculations per second.

Chalk that up as a win for science achieved through a loss at the chessboard.

Superhuman and perfect AIs

The Deep Blue style of simply throwing processing power at a problem has led to breakthroughs in most of America's popular board games. Often programmers don't even need supercomputers to claim victories. Normal laptops will do just fine.

•The same year Deep Blue battled Mr. Kasparov, an applications running on a regular PC took down the world champion in Othello in a six-game sweep.

•A Scrabble world champ fell in January to a nasty program written by Eyal Amir and Mark Richards at the University of Illinois at Urbana-Champaign. The code anticipates what letter tiles its opponent holds and finds ways to block possible high-scoring moves.

•Researchers at University of Alberta announced last month that they broke down the game of checkers into every possible position – all 500 quintillion of them (that's 5 followed by 20 zeros). The team had already written a checkers code that was superhuman, now their program is perfect. The computer cannot be defeated. The best an opponent can do is tie.

•Simpler games such as Connect Four and Tic-Tac-Toe were "solved" years ago.

Except for Scrabble, these examples are what artificial intelligence researchers call games of "perfect information."

"That means games where everything is right there in front of you," says Jonathan Schaeffer, chairman of the computer science department at the University of Alberta. "There are no hidden moves, no secret information."