A lot has changed from late 2016. Perhaps the most significant is that AI can now clearly defeat humans in heads-up big bet poker games. We can thank the research invested into subgame solving techniques for this. While many public software tools use a simple form of unsafe subgame solving based on assumptions (and are usually still effective), there are “safer” alternatives that provide theoretical guarantees for reducing overall exploitability which are more powerful still.

For example, the University of Alberta combined safe resolving with a neural network that can estimate EV values in their DeepStack AI. This agent can naturally play heads-up no limit hold’em at any stack depth and intelligently respond to any bet size it faces. Next up, Carnegie Mellon used the reach max-margin technique in their Libratus agent, which defeated human pros in the 2nd edition of Brains vs AI. Noam Brown continued to find many more optimizations for resolving, summarized in his award-winning paper. Well deserved and thanks for the acknowledgement.

There was a 2017 computer poker AI contest, but it was less competitive since the latest techniques require more computation than the contest rules allow. I submitted a slightly modified version of Act1 called Intermission, which ended up winning both the instant runoff and bankroll categories.

Looking ahead, people wonder if multiplayer poker (with 3+ players) will be the next target. It may be closer to reality than many expect…

The AAAI-16 instant runoff results were erroneous due to a bug unfortunately. The matches between the top finishers were re-run and a new order for the top 3 has been established. Tartanian8 actually repeated its victory from the previous tournament, forcing Slumbot into the second spot, and my entry Act1 into third. Congrats to Noam and the CMU team and condolences to Eric. Results and cross table.

Perhaps there will be news of another tournament soon…

This year it was Slumbot who edged out all others in the NLHE instant runoff event, built with a new memory-efficient technique called Compact CFR. My entry Act1 snuck into 2nd place, outplayed by a mere 0.6 bb/100 margin (ouch). Carnegie Mellon University, the team that hosted the Brains vs AI match, rounded out the top 3. Congrats to Eric, whose agent is free to play on his site www.slumbot.com.

The complete results with logs will be available shortly on the tournament website here (cross-table available here for now).

It was a treat to attend the AAAI conference and discuss our different approaches. I certainly learned a lot and hope to experiment with several promising ideas soon.

Over the next month, another edition of the AAAI computer poker tournament will take place. It’s all heads-up no limit hold’em this time around, still a game where humans can defeat AI — but for how much longer? I’ve entered an upgrade to my previous entry and expect many other competitors have done the same.