Murray Campbell

Winning against a computer isn’t in the cards for poker pros

human player versus poker bot
Computers can now defeat professional poker players at heads-up no-limit Texas Hold’em. Pro Jason Les (right) plays poker bot Libratus as computer scientist Tuomas Sandholm, one of the bot’s creators, looks on.

NO BLUFF

In the battle of wits between humans and machines, computers have just upped the ante.

Two new poker-playing programs can best professionals at heads-up no-limit Texas Hold’em, a two-player version of poker without restrictions on the size of bets. It’s another in a growing list of complex games, including chess, checkers (SN: 7/21/07, p. 36) and Go (SN: 12/24/16, p. 28), in which computers reign supreme.

Computer scientists from the University of Alberta in Canada report that their program, known as DeepStack, roundly defeated professional poker players, playing 3,000 hands against each. The program didn’t win every hand — sometimes the luck of the draw was against it. But after the results were tallied, DeepStack beat 10 out of 11 card sharks, the scientists report online March 2 in Science. (DeepStack also beat the 11th competitor, but that victory was not statistically significant.)

“This work is very impressive,” says computer scientist Murray Campbell, one of the creators of Deep Blue, the computer that bested chess grandmaster Garry Kasparov in 1997. DeepStack “had a huge margin of victory,” says Campbell, of IBM’s Thomas J. Watson Research Center in Yorktown Heights, N.Y.

Likewise, computer scientists led by Tuomas Sandholm of Carnegie Mellon University in Pittsburgh recently trounced four elite heads-up no-limit Texas Hold’em players with a program called Libratus. Each contestant played 30,000 hands against the program during a tournament held in January in Pittsburgh. Libratus was “much tougher than any human I’ve ever played,” says poker pro Jason Les.