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Researchers "Solve" Texas Hold'Em, Create Perfect Robotic Player
Jason Koebler writes The best limit Texas Hold'Em poker player in the world is a robot. Given enough hands, it will never, ever lose, regardless of what its opponent does or which cards it is dealt. Researchers at the University of Alberta essentially "brute forced" the game of limit poker, in which there are roughly 3 x 10^14 possible decisions. Cepheus runs through a massive table of all of these possible permutations of the game—the table itself is 11 terabytes of data—and decides what the best move is, regardless of opponent.
...they got banned by 6241 online casinos and bragging here is the only thing left?
Wouldn't another robot which knows of all possible decisions of this particular robot be better that this "Perfect Robotic Player"?
In theory there is no difference between theory and practice. In practice there is. - Yogi Berra
Recently I noticed that Texas Hold'em is only half of the game. The betting is the real strategic part. Unless the bot can do this well, I don't it will ever really "beat" a human player.
That is why it is limit poker. Besides all games have limits acknowledged or not.
Think of the robot as the house, it might not win everytime but it always wins in the long run.
From the article: "So, is online poker now dead? Destined to be crushed by robots? Not quite: No limit Texas Hold'Em—in which any amount of bet in any dollar amount can be made—is by far the most popular, and while robots can play that game quite well, we're no where close to solving it. Limit poker has roughly 3 x 10^14 permutations; no limit poker has 3 x 10^48, which is many orders of magnitude harder to solve."
Fantasy remains a human right; we make in our measure and in our derivative mode... -- JRR Tolkien
There is another computer that triples the bet every time it loses and leaves when it wins and says something about knowing when to walk away.
And then there is the computer that deals the cards and takes 4% of the pot every round, muttering "House always wins".
The third computer that can beat it keeps giving it complimentary alcoholic beverages until it gets a buffer overrun.
The fourth computer doesn't "believe in no win situations" and reprograms the computer to lose, but then Spock finds out and he gets kicked out of the Academy.
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
I'm a former professional poker player, now semi-pro and working again in the IT industry. In a game like poker, to "solve" the game, from a mathemartcal and game theory point of view, means to develop a strategy that is "unexploitable", which basically means "mistake free". If two game-theory perfect players were to play against each other, then their "expectation" would be zero, as if they were flipping a coin between each other. Neither would make a mistake, so only te randomness of the cards would determine the winner of a given hand. In the long run, both perfect players would win as often as they lose.
But in a real poker game, human players make lots of mistakes. A player who adjusts their strategy to exploit these mistakes will win vastly more than this (formerly theoretical) "perfect player". The game-theory optimal strategy is focused on not losing, rather than exploiting mistakes and winning the most.
So in an actual game, the expert human player will outperform the computer because the other humans in the game are exploitable.
In live play, especially in tournaments, computer solutions are used in poker. In particular, when the game is "heads up" (only two players), and the chips are not deep, which happens at the end of every tournament, then the correct strategy is to "jam or fold" all hands. The solution to this has been determined in a computer and top players have the table memorized.
If this subject interests you, I HIGHLY recommend "The Mathematics of Poker", by Chen and Ankenman.
You can better understand what is going on by considering the much simpler game Rock paper scissors. 'Perfect' here basically means the strategy gives you the best possible worst case.
For RPS, the perfect strategy (using the term in the same sense as it is used for the poker bot) is to play completely randomly. There is no way to gain an edge over this strategy, no counter-strategy which will give you more than 50% chance of winning, even if you know your opponent's strategy. (In this case, there is also no strategy which will give you less than 50% chance of winning against the 'perfect' strategy.)
For the poker bot, there is no strategy that will give you greater than 50% chance of winning against it in a two player game. If you know its strategy perfectly (but of course you don't know its cards) the best you can do is to equal that 50% chance (which is what happens if it plays itself.) Unlike RPS, you can can lose to the perfect poker bot by playing poorly. Also, as noted in the article, the perfect poker bot always plays as if it were playing against perfect opposition. A good human player will fleece you faster then the perfect bot, because the human player will notice your peculiar imperfections and exploit them, choosing to play in a way which would be suboptimal against a perfect opponent, but superior against you.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.