In what scientists are dubbing the first man-versus-machine poker championship, two professional poker players beat a University of Alberta poker-playing software program called Polaris in Vancouver.

Phil Laak playing in the World Series of Poker in Las Vegas, last year.
(Isaac Brekken/Associated Press)

The tournament began on Monday and ended late Tuesday. Two Los Angeles poker players ranked as the world's best, Phil (The Unabomber) Laak and Ali Eslami, won two out of the total of four rounds. One round was considered a draw and the software program did quite well, winning one of the four rounds.

About 1,000 scientists eagerly witnessed the contest, which took place at the annual conference of the Association for the Advancement of Artificial Intelligence. The tension was thick as the fourth and final round was the tie-breaker, with the computer and the humans having each won a previous round.

Jonathan Schaeffer from the University of Alberta, the lead scientist behind Polaris, told CBC news that in previous exhibition games, Polaris had lost so this week's win and draw over the human players was a real milestone.

Poker is a difficult game for computers to play since it involves gambling and deliberate deception — unpredictable variables that aren't easy to account for in software programs.

Over the two-day event, 500 hands of poker were played in what are called duplicate matches. "This means that the same series of cards will be used in the two parallel matches, with the two humans having the opposite hands in each match," said the school's website. Duplicate matches greatly reduce the natural variance in poker due to luck. 

"I'm one of the team members of Polaris and I've been sitting in the audience for two days watching the games, and I'm exhausted and I didn’t play a single hand of poker," commented Schaeffer.

The human players, Phil and Ali, felt it was the most demanding tournament experience they'd ever had, added Schaeffer. "They were both physically drained. The fact that they won the match just made the whole difference for them. They were elated and all the fatigue just melted away"

During the match, communication was forbidden between both the two humans, and between the separate copies of the Polaris program.

"The Man versus Machine match is a scientific experiment, and has been designed to gain as much statistical evidence as possible, measuring the difference in skill while factoring out much of the luck element inherent in the game of poker," said the University of Alberta website about the tournament. 

"It's inevitable that the computers will win. A few years ago, we had no chance against humans. Now, we're not better, but we're certainly competitive. I think that within a year, you'll see that the program will be noticeably stronger. And within a few years it's clear that computers will be better than humans — it may take five years or 10 years," he said.

Schaeffer also told CBC News that he's happy that the humans won, and that he's eager to repeat the competition as soon as possible — but that likely won't happen until six months to a year from now.

The University of Alberta has been doing research on poker-playing programs since 1992. It recently announced that it had successfully created a computer program that would never lose at the game of checkers.