Man vs. Machine: Poker-Playing Computer Falls to Pros

After first day successes in a two-day man vs. machine poker match, Polaris, a poker-playing computer, lost both games and the challenge against two professional poker players Tuesday night.

In the first poker challenge between humans and machines involving money, Polaris, a computer project created at the University of Alberta, took on two poker pros -- Phil "The Unabomber" Laak and Ali Eslami, two successful high-stakes players. On day one, the first match ended in a draw, but in the the second, much to the surprise of the team that created Polaris, the computer soundly beat its competitors.

But on the second day of play, the human players upped their games and posted decisive wins over the computer in both matches.

Despite the setback, the Polaris creators were pleased with the computer program's performance.

"We viewed ourselves as the underdog," Jonathan Schaeffer, the head of the university's computer science department, told before Tuesday's matches. "To come in yesterday and play as well as we did was just wonderful. No one really had any inkling that the program would play as well as it did."

The challenge, which took place at the conference of the Association for the Advancement of Artificial Intelligence in Vancouver, pitted Eslami, Laak and the computer against one another in two matches of 500 hands of limit Texas hold 'em each day. The matches were played at the same time in separate rooms. The computer and humans were all dealt the same cards for each hand, in an attempt to unequivocally prove who played the cards better -- the computer or the professionals.

In limit hold 'em, betting is structured and players are limited in the amount of money they can bet during each hand. Players can make $10 and $20 bets, and in order for a winner to be declared the player must win by more than 25 bets.

"It's very difficult for humans," Schaeffer said. "The pots were big. There was lots of money. When you're under a lot of pressure, it creates a lot of stress."

Schaeffer admitted that Polaris doesn't feel stress. "But the programmers do," he said.

Polaris actually consists of 10 different poker-playing programs, and the team behind the project has been working since 1991 with the goal of creating a "superhuman poker-playing program." During play, an additional program known as the "coach" chose which program Polaris will use to compete and, hopefully, win.

"The best results would be a really close finish that came down to the wire," Schaeffer said on Tuesday. "It will be entertaining one way or another."

Regardless of the outcome, Schaeffer said yesterday that he believed that his team has already learned the most important lesson: Polaris is competitive.

"We had no idea where the technology stood. We're not better [than humans]. There's not enough data to suggest that," he said. "It's clear that we're competitive."