Humans Beat Supercomputer at Poker – but Barely

Humans are still able to bluff and outwager their computer opponents around the card table. But the computer doesn’t blink.

Four of the world’s best Texas Hold ‘Em poker players squared off against a computer called Claudico during a two-week tournament at a Pittsburgh casino. Some $170 million was “bet” during the “Brains Vs. Artificial Intelligence” exhibition over 80,000 hands.

At the end, three of the four humans had more chips than the program – but their lead was not large enough to mean anything more than a statistical tie, according to the research team from Carnegie Mellon University, who arranged the tournament.

“We know theoretically that artificial intelligence is going to overtake us one day,” said Bjorn Li, the poker pro in the lead at the end of the 80,000 hands, in a statement released by the school. “But at the end of the day, the most important thing is that the humans remain on top for now.”

Li had amassed $529,033 individually, followed by Doug Polk at $213,671, followed by Dong Kim. Jason Les trailed Claudico by $80,482. Each of those players is ranked in the top 10 among Heads-up, No-Limit Hold ‘Em.

The computer played 20,000 hands each, one-on-one, against the four pros.

“We knew Claudico was the strongest computer poker program in the world, but we had no idea before this competition how it would fare against four Top 10 poker players. It would have been no shame for Claudico to lose to a set of such talented pros, so even pulling off a statistical tie with them is a tremendous achievement,” said Tuomas Sandholm, the school’s computer-science professor who directed the development of the poker machine.

The battles of man and machine have captivated the public’s imagination as computing became more and more advanced toward the end of the 20^th century. Eighteen years ago today, the IBM supercomputer Deep Blue beat chess grandmaster Garry Kasparov, which caused a mild sensation at the time, since the machine had become “smarter” than the man.

But chess has fewer unknowns, and poker is now considered a major test of artificial intelligence. Due to the bulk of unknown information, and the duplicitous behavior of the other opponents, the game is more complex – and forces adaptation through the course of a contest.

The computer showed no signs of being rattled after losing big hands, according to Polk, who won the tournament. But the computer still did not appear to be a top-notch player, he added.

“There are spots where it plays well and others where I just don’t understand it,” Polk said. “Betting $19,000 to win a $700 pot just isn’t something that a person would do.”

Claudico’s strategy – which occupies about two terrabytes’ worth of data – baffled even some of the computer scientists, they said.

During the tournament, local gamers came to the Rivers Casino to root on the best of the human players. Through the online stream, others watched from around the world, according to the casino.

The 80,000 hands recorded during the tournament will be used to improve the AI of Claudico, said Sandholm. The computer experts said they were confident the machine would soon outdistance the humans.