Tuomas Sandholm, a computer scientist at Carnegie Mellon University, is not a poker player--or much of a poker fan, in fact--but he is fascinated by the game for much the same reason as the great game theorist John von Neumann before him. Von Neumann, who died in 1957, viewed poker as the perfect model for human decision making, for finding the balance between skill and chance that accompanies our every choice. He saw poker as the ultimate strategic challenge, combining as it does not just the mathematical elements of a game like chess but the uniquely human, psychological angles that are more difficult to model precisely--a view shared years later by Sandholm in his research with artificial intelligence. "Poker is the main benchmark and challenge program for games of imperfect information," Sandholm told me on a warm spring afternoon in 2018, when we met in his offices in Pittsburgh. The game, it turns out, has become the gold standard for developing artificial intelligence.

Tuomas Sandholm, a computer scientist at Carnegie Mellon University, is not a poker player -- or much of a poker fan, in fact -- but he is fascinated by the game for much the same reason as the great game theorist John von Neumann before him. Von Neumann, who died in 1957, viewed poker as the perfect model for human decision making, for finding the balance between skill and chance that accompanies our every choice. He saw poker as the ultimate strategic challenge, combining as it does not just the mathematical elements of a game like chess but the uniquely human, psychological angles that are more difficult to model precisely -- a view shared years later by Sandholm in his research with artificial intelligence. WHAT I LEFT OUT is a recurring feature in which book authors are invited to share anecdotes and narratives that, for whatever reason, did not make it into their final manuscripts. In this installment, Maria Konnikova shares a story that was left out of "The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win" (Penguin Press). "Poker is the main benchmark and challenge program for games of imperfect information," Sandholm told me on a warm spring afternoon in 2018, when we met in his offices in Pittsburgh.

The night before his newest poker competition was set to begin, Carnegie Mellon's Tuomas Sandholm and his PhD student Noam Brown sat down to play a little No Limit Texas Hold'em against the main competition: the artificial intelligence program they designed called "Libratus." "I was totally wrecked," Sandholm told The Washington Post. But he is not a serious poker player, so that's not such a big achievement. For the past 13 days, however, Libratus has been facing off against four world-champion poker players in a Pittsburgh casino. If it can beat them like it beat Sandholm, it would be an enormous breakthrough.

A third of the way through a 20-day man vs. machine poker tournament, the artificial intelligence system has the hot hand. As of Wednesday at 2:30 p.m. ET, the humans and the A.I. system, dubbed Libratus, had already played more than 34,000 hands with about 120,000 hands likely by the end of the tournament. The "Brains vs. Artificial Intelligence: Upping the Ante" tournament kicked off Jan. 11 at the Rivers Casino in Pittsburgh. During the tournament, poker pros Jason Les, Dong Kim, Daniel McAulay and Jimmy Chou are playing Heads-Up No-Limit Texas Hold'em against Libratus. Libratus pulled ahead early, leading by a little more than $74,000 on the first day of play and by more than twice amount by Day 2. "This is quite nice given that in advance of the event the international betting sites considered us a 4:1 or 5:1 underdog," wrote Tuomas Sandholm, a professor at Carnegie Mellon University and lead developer on the Libratus system, in an email to Computerworld.

A third of the way through a 20-day man vs. machine poker tournament, the artificial intelligence system has the hot hand. As of Wednesday at 2:30 p.m. ET, the humans and the A.I. system, dubbed Libratus, had already played more than 34,000 hands with about 120,000 hands likely by the end of the tournament. The "Brains vs. Artificial Intelligence: Upping the Ante" tournament kicked off Jan. 11 at the Rivers Casino in Pittsburgh. During the tournament, poker pros Jason Les, Dong Kim, Daniel McAulay and Jimmy Chou are playing Heads-Up No-Limit Texas Hold'em against Libratus. Libratus pulled ahead early, leading by a little more than $74,000 on the first day of play and by more than twice amount by Day 2. "This is quite nice given that in advance of the event the international betting sites considered us a 4:1 or 5:1 underdog," wrote Tuomas Sandholm, a professor at Carnegie Mellon University and lead developer on the Libratus system, in an email to Computerworld.

A third of the way through a 20-day man vs. machine poker tournament, the artificial intelligence system has the hot hand. As of Wednesday at 2:30 p.m. ET, the humans and the A.I. system, dubbed Libratus, had already played more than 34,000 hands with about 120,000 hands likely by the end of the tournament. The "Brains vs. Artificial Intelligence: Upping the Ante" tournament kicked off Jan. 11 at the Rivers Casino in Pittsburgh. During the tournament, poker pros Jason Les, Dong Kim, Daniel McAulay and Jimmy Chou are playing Heads-Up No-Limit Texas Hold'em against Libratus. Libratus pulled ahead early, leading by a little more than $74,000 on the first day of play and by more than twice amount by Day 2. "This is quite nice given that in advance of the event the international betting sites considered us a 4:1 or 5:1 underdog," wrote Tuomas Sandholm, a professor at Carnegie Mellon University and lead developer on the Libratus system, in an email to Computerworld.