Humans are funny creatures in a lot of ways. One of our quirks is that we seem to mind less when we know we’re getting ripped off than when we suspect we might be. Even as we wring our hands about the possibility of our online opponents not actually being human, it seems that there is sufficient interest in playing against a known computer opponent – even an unbeatable one – that digital human-vs.-AI poker machines have been developed and deployed in Las Vegas in recent years.
Early this year, the news came out that heads-up Limit Hold’em had been effectively solved by researchers at the University of Alberta with a bot known as Cepheus. Later, the humans clawed one back as a team of four led by Doug Polk managed to defeat the No-Limit bot Claudico, developed by Tuomas Sandholm at Carnegie Mellon. There’s a sense, however, that this victory is bound to be short-lived, as the encroachment of digital algorithms into previously human areas of expertise has thus far been relentless and uni-directional.
Slot machine company IGT rolled out heads-up limit Hold’em machines for use in Las Vegas back in 2010. Reports are that the first versions may have been beatable, and it seems that at one point they were yanked and later replaced, possibly for that reason. In the post-Cepheus world that’s likely a vain hope, and the latest versions have been charging a small rake just to make extra sure.
The problem for both IGT and the academic researchers into poker AI has always been, however, that one-on-one games are much more easily attacked than multiplayer games. The reason for that is essentially the possibility of collusion: Even in theoretical terms, there is typically no perfect strategy for a single player in a game with three or more interacting parties, because the others can end up cooperating to defeat it, whether explicitly, or due to coincidentally synergy of their strategies.
Of course, if you have five AI bots playing against one human, then the solution for optimal play is just to have the bots collude. In fact, even if you didn’t do it – even if you promised that you weren’t doing it – people would still assume that’s what was going on, especially when they happened to be on a losing streak. The weird solution that IGT has come up with is to create a new line of 6-max “Fold Up” machines. What that means is that the computer players’ hole cards are turned face up as soon as they fold; this gives the human player an edge in terms of seeing what outs are dead, but more importantly, it’s meant to alleviate paranoia by letting the player see exactly what the bots are up to.
IGT’s promotional materials for the machine make no mention of the bots’ strategy and whether they are working together. Based on a first-hand report from someone who tried the machines, however, it sounds like the bots’ play does in fact involve whipsawing the player on later streets when one bot holds the probable-best hand; the other will then continue reraising in order to cap the betting, even when its own hand has no chance of winning the showdown. I guess that the hope is that players will appreciate the honesty and perhaps imagine that their informational advantage in seeing the folded cards could be leveraged to beat the bots’ cooperative play.
In fact, it seems like the bots are intentionally beatable before the rake is factored in, and tend to make a lot of loose, fishy plays. The key phrase there is “before the rake,” however, because these machines have an insane 25% rake, capped at nine “units,” equivalent to four-and-a-half big blinds. This, too, explains the bots’ loose play; since they’re playing for the house, it’s in their interest – and against the player’s – to make sure that the rake cap is hit as often as possible. If, in the process, the player can be given the impression that he’s playing better than his opponents, so much the better.
In other words, IGT has managed to condense the online microstakes experience into slot machine form: a table of terrible, splashy, possibly-colluding opponents who like to show you their cards and yet still can’t be beaten because of the prohibitive rake. That doesn’t sound very appealing to me, but I live in a country where I can still play online if I like; I can see how splashing around at a digital table for a few bucks could be fun and nostalgic for the US audience, particularly those who are just in Vegas for a visit and don’t have an account at one of the legal online poker rooms operating there. If you want to give Texas Hold’em Fold Up a try, it’s at Harrah’s on the Strip.
Alex Weldon (@benefactumgames) is a freelance writer, game designer and semipro poker player from Montreal, Quebec, Canada.