Humans Can Still Out-Bluff Machines

Pcol writes "The New York Times reports that in a poker game this week between man and machine, a program called Polaris fought a close match, but lost to two well-known professional poker players. Designing a poker playing algorithm is a different and more difficult challenge for software designers than chess and checkers because of uncertainties introduced by the hidden cards held by each player and difficult-to-quantify risk-taking behaviors such as bluffing. The game-tree approach doesn't work in poker because in many situations there is no one best move and a top-notch player adapts his play over time, exploiting his opponent's behavior. Polaris build a series of "bots" that have differing personalities or styles of play, ranging from aggressive to passive. Researchers monitored the performance of three bots and then moved them in and out of the lineup like football players."

Not harder than chess

[jshriverWVU]

In poker you have a finite number of cards, that are a lot smaller than the permutation of moves in chess or checkers. Just the ability to count cards and do statistical analysis makes poker, blackjack, etc easier to compute in my opinion. Then again, if you had a deck of random cards and not a standard deck, that would make it a bit harder but that's not how it's really played. That would be like comparing it to chess with all queens.

Re:Not harder than chess

[TheMeuge]

If you're playing cards in Hold'em, against decent players, you WILL lose.

Hold'em is all about betting - if, when, and how much. And THAT you determine by the behavior of your opponent. It's not a strategy game, but a psychological exercise.

Re:Not harder than chess

[xero314]

[poker is] not a strategy game, but a psychological exercise.

Poker is indeed a strategy game. Knowing statistics and probability are critical to successful poker play. Psychology is important was well but is useless with out strategic knowledge. The majority of poker played in the world is limit poker which has far less psychological play and a lot more statistical accuracy. Even in a No Limit Hold'em game, probably the most psychological game regularly played, you would be better off having strong strategic and analytical skills an poor psychological skills than the other way around. But, like any game which contains aspect of chance, both strategy and psychology are imperative to being a successful player.

If you're playing cards in Hold'em, against decent players, you WILL lose.

I would be happy to take on any player, no mater what there record is, as long as that player never looks at his hole cards. Cards are important in card games, even if betting is the determining factor in who ultimately takes a particular pot. Imagine the game being played with no cards what so ever and you will see why knowing how to work with the cards you have is important to the game. Any time a professional player makes a "call" it is because of statistical knowledge and not psychological, even if it is to set up a play later on.

Re:Not harder than chess

[c_jonescc]

Being that the CS folks that setup the computer were expecting a draw, I think they must have started with the assumption that a top level pro poker player knows the statistics of almost every situation (from experience and intuition) as well as a machine can calculate them. And the truth is they do - the best probably know what their hole cards and flop mean down to the first decimal point every single time it's worth thinking about.

So, then the play comes down to responding to how the other person is playing. And the edge goes to the one that can safely be unreadable/unpredictable/inconsistent.

Now, obviously if you can't figure out any of the statistics involved in a hand you will always get your ass handed to you in the long run by a player/machine that can do the most rudimentary calculation.

Re:

[xero314]

I'd venture to say that pot-limit omaha high is a *far* more psychological game

I agreed 100% and would put most stud games even above omaha in the amount of psychology in the game, but I said "played regularly" which from my experience limits the games to Texas Hold'em, Omaha hi/lo and 7 Stud hi/lo, and usually only limit for the later two, since they are the most common spread games, at least in the united states. I have actually never seen a Pot Limit Omaha High game in any casino I have been in and that's not a small number (though I am holding an HA rotation next week so I am cer

Re:Not harder than chess

[SIIHP]

"I'd venture to say that pot-limit omaha high is a *far* more psychological game."

You'd be wrong. I made my living for two years playing PLO almost exclusively, at a high level (fuck you UIGEA and everyone who voted for you). The general consensus among students of the game is that PLO is one of the least psychological games played. The lack of bluffing being the major reason. Bluffing occurs, but the very same reason you cite as making it more psychological is why you're wrong the number of hands played. Playing such a large number of hand (50% is insane, and I challenge you to show me some poker tracker stats of someone who wins playing 50% of their hands long term). In fact, if a computer were to win consistently, I think PLO is a game that it would play.

"I don't think there's a difference between statistical knowledge and psychology."

Then let me learn you up. Let's use PLO. I have A-A-10-J double suited. I raise pot preflop. A VERY tight player reraises, and I call. Flop come K-K-K. Against an aggro player, I can reasonably infer that my 2nd nuts is good. Against Mr. Tighty, who I have seen reraise only with large suited pairs (KKJQ, QQJ10) or rundown hands (9-10-J-Q, 10-J-Q-K) I know within a certain range what he's holding, with some certainty. I am first to act, I check, he bets, I raise, and Mr. Tighty RERAISES. Based on my assessment of his likely behavior (psychology) I can reasonably infer that he has the K. Statistically, you NEVER lay down K's full of A's, but when your read (psychology) is good and the opponent is uncreative and direct (psychology) you lay it down.

Statistically the correct play is to put it all in if you can, but by understanding the other players decision making process (psychology) you can find a fold.

You're wrong again

Re:

[xero314]

Statistically, you NEVER lay down K's full of A's...

If you actually think this is true you are using some bad statistics. I don't think that you do think it is true as you said yourself you would fold in the described situation. Even if you are taking all other information out of the equation statisiticaly K's full of A's (with 3 Ks on board) will lose approximately 1 in 11 times (opponent has 4 chances to have a king out of the 45 unseen cards). This means statistically you should lay down kings full of aces 1 out of every 11 times you play, but you woul

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[Bender0x7D1]

I think the point is that you don't know if it is the 1 time you lose, or the 10 times you win, so you would go for the win since, 10 out of 11 times, you would win. Who cares if you lose that 1 time if you win the other 10 times. That's why you never lay them down since, statistically, you are 10 times more likely to win than lose.

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[joss]

Sancitmonious tripe. Those who lose money from poker do so voluntarily
so its a a form of entertainment they pay for. Professional poker
players are no more a leach on society than opera singers.

Old joke ,,,

[Tungbo]

Father explains the statistics of roulette to his son.
He shows how in the long run, all players will lose to the casino.
His son nods and nods with his explanation. At the end,
the father said, "Well son, have you learn anything from this lession?"

"Yes indeed. I'm going to open a casino when I grow up!"

Re:Not harder than chess

[xero314]

There are plenty of times a pro player makes a call believing they have the worst hand, in order to bluff the hand later.

You are correct, but again this is because of statistical knowledge. A good player has determined in their own head what they believe the statistical chances are of their opponent having both a hand they can't call with and their opponent will believe that they themselves have a winning hand. Not only that the player making the call also has to determine if they odds are correct to try and set up a bluff like that in case their opponent has a draw and how good that draw is. If you are making any move in poker without first making a educated guess as to the odds, and determining that those Odds are in your favor, then you are leaving your odds up to chance and this is not how to be a successful player.

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[Abcd1234]

It's not a strategy game, but a psychological exercise.

You tell yourself that. But it's BS. Poker, when it comes down to it, is all about a) statistics, and b) luck. Is there a psychological component to it? Sure. But I'll bet dollars to donuts those aspects are greatly outweighed by luck and a given player's ability to evaluate the statistics on a given hand.

Re:Not harder than chess

[Aaron England]

Thinking that poker is only about statistics and luck is the hallmarks of an inexperienced player. The simple truth is, if you make your bets on the odds that you will win the pot against a professional poker player you will lose with 99.999% certainty. Because a professional poker player doesn't just play the odds, he plays you. He does this by lying about the strength of his hand through bluffing and discerning the times you attempt to bluff. Here's an example of how your stategy would play out. Let's say the following happens on the river.

You: Pair of 2's, check
Him: Ace-high, all-in

Now do you call or fold? You have the better hand here. If you knew what your opponent had you would definitely call. But since you are playing the odds, you decide to fold because you calculated you have a 30% of winning, which also means you have a 70% of losing. This is why playing the odds will cause you to lose. This is why it is the "psychological exercise" that the grandparent said it was.

Re:

[Propaganda13]

psychology - the study of mind and behavior in relation to a particular field of knowledge or activity

Just because it's not about you wanting to have sex with your mom doesn't mean it's not psychology.

Pre-flop odds are all calculated on what your hand is. Statistically you know your chances on winning are. Your opponent's hand doesn't matter to you since it's unknown to you and doesn't factor into the odds.

Re:

[Brickwall]

I watch a lot of poker on TV, and I'm constantly amazed at how often Daniel Negrenau can call his opponent's hole cards correctly.

In a magazine profile, the writer played heads-up with Daniel for two hours. After the first half hour, Daniel was calling the writer's hole cards with astonishing accuracy.

You may not want to use the term psychology to describe this skill, but millions will disagree with you.

Re:Not harder than chess

[drfireman]

You tell yourself that. But it's BS. Poker, when it comes down to it, is all about a) statistics, and b) luck. Is there a psychological component to it? Sure. But I'll bet dollars to donuts those aspects are greatly outweighed by luck and a given player's ability to evaluate the statistics on a given hand.

One of the chief reasons there are winning poker players is that there are lots of players out there who are willing to bet dollars to donuts without knowing what they're talking about. There are experienced poker players who would agree with you. They're usually pretty bitter, because they can't understand why despite having learned the statistics and having played a large enough number of hands for their skill to win out, they're long-term losers to those of us who've taken the time to understand it better.

In limit games against unskilled opponents, you're right. In other games, the psychology is much more important. And in fact, if you want to do the probabilities right, you need the psychology. There's almost no hand of interest you can analyze properly without an estimate of some quantity like "the probability this bozo would make that raise in this situation." Is it statistical analysis or psychology? Is it the sugar or the stirring?

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[Dan D.]

It's not a strategy game, but a psychological exercise.

One could imagine that a "psychological exercise" is still a strategy game, but with much wider priors in the statistics.

As Negreanu put it

[vlad_petric]

... absolute probability will only get you so far in poker. After that, it's conditional probability.

(not an exact quote)

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[Normal Dan]

Far harder than chess. In chess, every permutation has a low number of values (every turn has few possible moves). In poker, every turn has a large number of possible moves/choices, such as how much to bet. Also, in chess, you can see the other players hand, in poker you cannot. This adds to the complication of poker. If this weren't bad enough, bluffing adds a whole new set of problems. Also, in chess, given enough computing power, you can process all the moves up until the end of the game. This is

Re:

[raehl]

Also, in chess, given enough computing power, you can process all the moves up until the end of the game.

That's not entirely true - you can theoretically process all the possible moves, but, you still won't know the result until you know what the hole cards are.

In chess, the player's moves determine what happens on the board. In poker, you can't change what happens on the board; you can only change how much money you win or lose as the game progresses.

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[BlowChunx]

...excuse my ignorance, but I thought the limit only applied to the maximum bet (meaning no "all in" bets).

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[xero314]

I thought the limit only applied to the maximum be

That would be spread limit as opposed to fixed limit which is what they were actually playing. Most flop/board/community poker games played around the world are fixed limit, though stud games tend toward spread limit.

Re:

[jshriverWVU]

Not sure why I was marked Flamebait, I have written a poke playing program, and spent the last 6 years developing a chess engine. (Though lately I've been migrating to Go) meant what I said for better or worse, wasn't flaming.

Re:

[Otter]

In poker you have a finite number of cards, that are a lot smaller than the permutation of moves in chess or checkers.

First of all, moderators, this is mistaken, not "Flamebait".

Second, you're correct that the cards are trivial to calculate. The betting process in poker is what's much more difficult to model.

Watching it occasionally on ESPN, I see people who are presumably good enough to be on television doing things that are completely insane. (Why the hell would anyone go all-in with unsuited 8-3?!?) It

Re:Not harder than chess

[AuMatar]

Because there's more to a situation than your cards. There's your chip stack, your blinds, the action behind you, your opponents chip stacks, the payment structure, and your position. Pushing on 8-3 unsuited is a poor move, but there's at least two situations where it's called for- if you're far from a money boundary in the payment structure, have a small number of chips in compared to the blinds (say an M of 3-5), and all players before you folded. In this case, by pushing in you're likely to win the blinds. Especially if none of your remaining opponents have a big stack. The risk can be worth it, since it makes absolutely no difference what hand you go out on unless you reach a new money boundary, and you'll have to win at least 1 hand to do so. And with 83, you're likely to have 2 live cards if called by a high ace (AK, AQ, AJ, AT). Note that you'd only want to do this if first into the pot- someone who called the blind is too likely to call you for only an additional 2-4 big blinds.

The other situation to try it in is a squeeze play- if you have a raise and a call behind you, you have a very tight table image, and you think they don't have good hands. A raise, especially an all in raise, is signaling an extremely good hand. From a tight player, this must be respected. You can get both players to fold here if they don't have premium hands (AK, QQ-AA). This is a high risk move though, and you must have been playing extremely tight, versus people capable of laying down a good hand, to try it.

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[Otter]

Watching pro athletes ("athletes", in this case, in the ESPN2 sense), everything looks misleadingly easy, and the people I'm thinking of got crushed in a way that certainly looked easy. Against normal players, yeah, I'm sure you're right that it could work if done well.

Anyway, all this reinforces the point that modeling poker is *hard*.

Re:

[SatanicPuppy]

Saw one once where a guy was standing on a suited pair and had nothing but garbage until the last card dropped, at which point he had a straight flush. Cleaned out his opponent because the guy was just damn sure that there was no way an intelligent person would have stood on the two cards that he would have needed to stand on to make a straight flush.

I thought the loser was going to start a fight when he left the table. Entertaining. One of the things about humanity is that we're willing to take a chance on

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[Sparr0]

A suited pair? What? Obviously you don't mean a pair, from context. Try to get it right next time.

Re:

[SatanicPuppy]

Yea, I think he was really pushing a bluff, and the other guy cottoned to the fact that it was a bluff, and then suddenly it wasn't a bluff anymore and he got schooled.

poker jargon pedantry

[mr_mischief]

"is this game honest?"

well, no. not if the guy was dealt a "suited pair" from a single deck.

There's no such thing as a "suited pair" in a single deck.

You have four distinct suits, and thirteen distinct ranks. There is one card of each of the thirteen ranks in each suit, and likewise there is exactly one card of each suit at a given rank.

A "pair" is two cards of the same rank. "Suited" means two cards of the same suit. So to have a "suited pair", one must have two cards of the same rank and the same suit.

The

Re:

[Kjella]

(Why the hell would anyone go all-in with unsuited 8-3?!?)

Because when you're bluffing, you don't bluff half-way so they'll call you on it (as opposed to when you're not bluffing and want to fish for more chips), and if someone with a top hand decides to call you on it, your medium hand will probably lose anyway. So if you're looking to make the others fold, unsuited 8-3 is as good a bluff as any other hand. Besides, if you're in a squeeze and hit the right company you can still win and get back in the figh

Re:

[wildsurf]

It seems like the problem here might be the helplessness of artificial intelligence in the face of natural stupidity.

Douglas Adams invented a word for this:

ABOYNE (vb.) [langmaker.com] To beat an expert at a game of skill by playing so appallingly that none of his clever tactics or strategies are of any use to him.

Much harder than chess.

[raehl]

In chess, each player knows where all the pieces are and knows all the moves available.

In poker, neither player knows where all the 'pieces' are.

So the problem the computer has to solve is totally different. In chess, the computer has to compute the best next move. In poker, the computer has to determine if it's hand is better than the opponent's hand, AND if its hand is better, win as much money from the opponent as possible, AND if its hand is weaker, lose as little money as possible, OR convince the op

Re:

[Digital Vomit]

In poker you have a finite number of cards, that are a lot smaller than the permutation of moves in chess or checkers.

Maybe so, but in chess and checkers you can see the other person's pieces.

Re:

[debrain]

In poker you have a finite number of cards, that are a lot smaller than the permutation of moves in chess or checkers. Just the ability to count cards and do statistical analysis makes poker, blackjack, etc easier to compute in my opinion. Then again, if you had a deck of random cards and not a standard deck, that would make it a bit harder but that's not how it's really played. That would be like comparing it to chess with all queens.

The effect of counting cards is decreased by not playing the back-half to

Re:

[toleraen]

That's one lucky king~

Re:

[packeteer]

Your point is right but some of the things you say are a little off.

This is beyond simple mathematical calculations and hence it's MUCH harder than chess.
Chess is much more than just simple calculations. It is full of very complex calculations. Because of the incredibly huge number of moves possible it is more than just calculating. The best computer chess programs calculate less and use pattern recognition more. These days a computer with a fraction of the computing power of Deep Blue would beat it. T

Re:

[xero314]

everyone plays in certain patterns and even when someone tries to change their own game they do it in their own personal way

Many good players use game theory and randomization to actually remove their own personality from a certain percentage of their plays. Beating a computer that is using pattern recognition is still very easy and will be for the foreseeable future. Imagine in for 1 out of every 5 decisions a player needs to make during a poker match that player flips a coin to determine their action. The computer may eventually be able to determine that the 5th action will always be random, but one it won't help and two y

Re:

[Relic of the Future]

That's a good point. If a computer can win at Rock-Paper-Scissors (and it can), then poker should benefit from the same ability to predict the oponent's action based on past actions.

yea well

[jimbug]

let's see how well those computers do in strip poker!

Re:

[NeoTerra]

That all depends on if it has an internet connection or not ;)

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[sa1lnr]

Mine has to play with a handicap. The side panel is already off.

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[Dachannien]

Fry: Uh, yeah, look at that exhaust fan!
Flexo: Augh!
Bender: Pervert!

Only expert players ....

[gstoddart]

I got the impression from some of the news stories that two professional poker players barely beat out the machine.

I have a sneaking suspicion that, for the vast majority of players, the computer is gonna kick your ass quite handily.

For the same reasons, I suspect that everyone who wasn't at the level of Kasparov would have gotten their asses handed to them in a game of chess against older versions of computers which couldn't yet beat him.

This, of course, begs the question of how long it will take for the on-line casinos to start putting poker playing bots into the mix to skew the odds even further to the house. I mean, if you have a computer program which will beat everyone else, why not just dial it down so it only wins 30% of the time or so and nobody will be any wiser.

Cheers

Re:

[CrazyJim1]

I got the impression from some of the news stories that two professional poker players barely beat out the machine

In poker, professional players barely beat out amatuers nowadays.

My friend and I wrote an interesting poker program which sets up a table of 10 on a standard sit and go style table, and plays through 10,000 iterations to see which bot is the best.

Me, being the slacker, never made any bots to play his so it kinda fizzled out because I'm a bum... But it did have potential.

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[gstoddart]

In poker, professional players barely beat out amateurs nowadays.

Allow me to clarify ... how's professional-level or exceedingly talented amateurs grab you? Playing poker full-time wasn't really meant to be the thing which differentiated.

The reality is, pro or amateur, the overwhelming majority of users would NOT come anywhere close to winning against this program. They simply wouldn't have the skills at poker to even come close.

Cheers

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[suv4x4]

This, of course, begs the question of how long it will take for the on-line casinos to start putting poker playing bots into the mix to skew the odds even further to the house.

If they would put bots to play against you in a casino, they'll need more bots to grab you in the middle of the street and threaten with death if you don't come inside and play.

The idea of a casino is, it seems plausible you may win. It's very important to keep that plausability.

As for computations, they are ALREADY used in casinos, t

Re:

[zipwow]

I think the point is that if you're an online casino, you're already making money by taking a "rake" of each poker hand (nobody plays the house).

It would be very tempting to add bots to the game in order to add a house cut. And who would know?

-Zipwow

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[AuMatar]

There are no house odds in poker. You don't play vs the dealer, you pay for time, either in the form of a rake on the pot or in the form of up front payment. So there's no reason to try and skew the odds. If anything,t hey'd liek the games to be wilder- bigger pots=more rake. And the more the money flows around the table, the more chances they have to take it.

The Poker Bots already exist

[miller60]

Poker bots have been deployed at major online poker sites for years now. There was media coverage of this trend back in 2004 [msn.com] and 2005 [wired.com]. The real issue is that the online poker sites have to ensure they aren't American poker bots, lest they run afoul of Bush administration policy.

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[Animats]

For the same reasons, I suspect that everyone who wasn't at the level of Kasparov would have gotten their asses handed to them in a game of chess against older versions of computers which couldn't yet beat him.

Current reality is that any of the better [wikipedia.org] chess programs [wikipedia.org] for PCs can trounce you, unless you've been on the cover of Chess Life. Grandmasters are now playing Rybka with Rybka handicapped by one pawn, or with no opening book, and still losing fairly often. It's clear that computer chess performa

Hang on a Minute...

[bateleur]

The implication here is that there is no (known) equilibrium mixed strategy for bluffs (because if there were then Polaris could be coded to use it).

Is that really true?! It seems very counterintuitive.

Certainly there's nothing special in general about games involving bluff. One of Von Neumann's first game theory case studies involved a simplified version of poker precisely to demonstrate how to automate bluffing.

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[UbuntuDupe]

It seems very intuitive. For each bluffing algorithm (hand->bet correspondence), it seems there would be one that beats it, and then you'd have a sort of rock-paper-scissors cycle.

Perhaps if you randomly bluffed, with an x% chance of bluffing on a given hand, and the rest of the time bet on the true merit of the hand?

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[roscivs]

It seems very intuitive. For each bluffing algorithm (hand->bet correspondence), it seems there would be one that beats it, and then you'd have a sort of rock-paper-scissors cycle.

And computers, interestingly enough, tend to do better at rock-paper-scissors than humans. For example,
http://chappie.stanford.edu/cgi-bin/roshambot [stanford.edu]

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[bigdavex]

he implication here is that there is no (known) equilibrium mixed strategy for bluffs (because if there were then Polaris could be coded to use it).

Is that really true?! It seems very counterintuitive.

I think there are known equilibrium mixed strategies for some situations involving bluffs, just not the entire game.

Re:Hang on a Minute...

[Shaterri]

Simple bluffs are pretty straightforward to handle, but the combination of factors in poker (multiple rounds of action, shifting hand strength, complex unknown information) makes it inordinately difficult to compute Von Neumann optimal strategies. Even simpler games like (0,1) poker (both players are randomly 'dealt' a number in the 0..1 range, smallest number wins) with multiple betting rounds are remarkably difficult to solve under normal betting patterns. For more information, I heartily recommend The Mathematics of Poker by Chen and Ankenman.

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[zCyl]

Is that really true?! It seems very counterintuitive.

It seems to me that bluffing is a reactive or anticipatory activity. The optimal strategy would therefore depend on what strategy the other player is using. Since the other player can choose any arbitrary strategy, this does not seem like an easily solvable problem.

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[Kjella]

In theory, I'm sure it is... so that you as on the betting end go:

Under these conditions:
10% 50
20% 150
30% 350
20% 700
10% 1500
5% 3000
5% 10000

And then on the evaluating side, under these conditions a bet of 700 means:
nothing: 30%
one pair: 20%
two pairs: 20%
three of a kind: 20%
better than that: 10%

Unfortunately, it's not quite that simple. For one, who's sitting on the blinds, how many have called or bet and by how much and how many have folded, are you before or after the other guy, what's my chip stack and wha

Re:

[Phleg]

Bluffing, like the widely-held understanding of tells, are way overestimated in their value to the game.

By far the most valuable skill in poker is people reading. Not looking for tics, flinches, or whatever, but by understanding how they react to situations. How do they play flush draws? What kinds of cards will they play with given an under-the-gun raise, when in mid position? What size bets will they call with mediocre hands, and what size bets will they fold strong hands to?

These are far, far more im

Looks like it'll be this way. . .

[Astro HJX]

I think that it'll probably stay this way for a while - man beats machine, altho as been talked about before when someone got beat in chess by one. I can't remember the name of it, but I'm sure others know. I'll be impressed once computers can out-think human beings totally.

probability

[ejito]

Seems like a computer's ability to compute probability should win in the long haul. Dealing with bluffing seems moot when you can compute cash flow stakes using something like a markov chain.

How far we've come.

[Rob T Firefly]

Dealer: My deal..
Eliza: What does that suggest to you?
Dealer: It suggests I'm giving you your cards.
Eliza: We can talk about me later. Now back to you...
Guest: Here you go.
Eliza: So you feel I go...
Guest: Um.. yeah. How many cards do you want?
Eliza: What else comes to mind when you ask that?
Dealer: You need to give me whatever cards you want to exchange.
Eliza: I see. Tell me more.
Dealer: Um.. so you can get a better hand?
Eliza: We were discussing you--not me.
Dealer: Do you have any interest in playing this game?
Eliza: Oh, I have any interest in playing this game?
Dealer: That's it, I quit! Go find someone else to torture!
Eliza: That would't help much, now, would it?

Minimax

[Mayhem178]

The game-tree approach doesn't work in poker because in many situations there is no one best move and a top-notch player adapts his play over time, exploiting his opponent's behavior.

I believe that the summary is referring to a "minimax" tree here. In a perfect information game (which most forms of poker technically are), you can construct a tree, each tier of which contains every possible "move" that the active player can make during that turn (each of these "moves" are nodes of the tree). Each node

Once again, the computer cheats

[mcmonkey]

(Or rather, the people using the computer cheat.)

From one of the rounds of human-computer chess matches of recent years, I remember something about the computer analyzing previous games played by the human opponent, while the human was given no such background on the computer. Studying an opponent's history of play is accepted; the issue here is one side had this aid while the other did not.

Anyway, in this case,

Unlike computer chess programs, which require immense amounts of computing power to determine

Re:

[dj_tla]

But Polaris is a single bot that can adjust its style of play. It just does this by asking a bunch of other bots what they would do, then decides its action based on the other bots' past performance and some other metrics. Your argument doesn't really make any sense; there are no people using the computer during the match, the bot is completely autonomous other than someone pressing the start button.

Re:

[kalirion]

I'm sure contests like this are lots of fun, but for this to be a serious contest, either the programmers need to come up with a single bot that can adjust its style of play, or we find a human with split personalities that are all expert poker players with different styles.

I thought top-tier players were supposed to be able to change up their game style at the drop of a hat in order to prevent others from reading them?

I'm stupefied

[suv4x4]

So computer may lose in a game that has certain amount of pure randomness in it. I'm shocked.

What the article misses is that if there was an actual android having camera eyes and being allowed to use its full processing power, it'd simply count the cards and beat every single damn time.

But sure, introduce noise and win sometimes if it makes you better. They gotta introduce dice rolling in chess as well:

"Haha, HAL, you threw an even number, which means I take your queen for no reason at all and you can't do

Re:

[Crazy Man on Fire]

There's very little benefit to counting cards in Texas Hold 'Em since so few cards are shown and the single deck is reshuffled between hands. Everybody at the table has access to the same information by just looking at the board. Only the two cards in front of each player are private information. You're really just playing pure statistics (relatively easy to calculate) and reading your opponents (very difficult, especially for a computer).

Re:

[suv4x4]

You can't count cards in Texas Hold'em. The single deck is shuffled every hand.

I don't mean count literally. In any way recognize the card order. It may even be about specs on the back of each card invisible with simple eye.

Computers can scale and improve their detection detail by simply tacking on a better/faster device to use. Humans have to do with their own eyes/brain.

Can we really?

[feepness]

Maybe that's just what they want us to think?

Playing the long-con.

stratego, l'attaque, dover patrol, tri-tactics etc

[hedley]

Games with imperfect information. Very hard to design good AI to play these games, as the story says, tree search is not a win here. A game like stratego also has concepts that go beyond individual piece movement, i.e. you may want to group an few pieces together to make an attack, moving the unit (subject to input from the enemy) forwards. I have yet to see a good stratego game, there is one for $ called "The General". It can be defeated quite easily. I have found a stratego game in the past that could *not* be defeated! But, some sleuthing on my part (via saving the game and restoring it at key points) showed the sw was cheating by moving its pieces around to adjust to the threats(!). I have had an obsession with this style of AI but its such a daunting problem its hard to get a good handle on where to start to chip away at it. I suspect the polaris folks have been doing just this, the AI and methods they develop would be useful for other games I am sure.

H.

More info on Polaris

[dj_tla]

For those curious about the bot, Polaris is being developed by the University of Alberta GAMES research group [ualberta.ca]. Polaris' implementation is discussed in detail through publications hosted on the Poker group's website [ualberta.ca]. The U of A's coverage (including video interviews of the participants) can be found here [ualberta.ca].

Chance elements make this hard to judge

[_bug_]

Poker has elements of chance. Chess does not. You can play the odds to help minimize the risk of chance, but it's still there. That one two or even 5 games resulted in a win for side A versus side B is pretty much meaningless. With chance involved you really need to conduct this sort of experiment over thousands, if not millions of games, to even begin to get a handle on if there really is a "better" player in the computer code.

You can flip a coin 5 times and all 5 might be heads... doesn't mean that heads

Re:

[Archangel Michael]

"That's chance. That's poker, even if the pros and the weekend wannabes try to argue otherwise."

Poker has an eliment of chance, however chance doesn't explain why you consistently see the top pros at final tables. A poker pro will know how to do the following ...

1) Read another player
2) Know how to maximize reward compared to risk
3) Adjust play to compensate for 1 and 2

Poker is a game of skill with chance invovled. Since Chance is equal (over the long haul) between all players, chance doesn't explain repeat

Re:

[Abcd1234]

Poker has an eliment of chance, however chance doesn't explain why you consistently see the top pros at final tables.

Who are also quite frequently tossed out in the first round.

No, it's not entirely luck. Pure number crunching skill is also quite important, both in calculating the odds, as well as in determine risk-reward for a given situation, deciphering player's betting strategies, etc. Such skills take time to master, so it's hardly surprising that the more experienced, practiced players typically per

Environmental Sensors

[jshriverWVU]

Would be nifty if the bot's had access to environmental sensors like a camera so it could do facial recognition on the people to detect twitching, detect very little sweating, excess heat coming off body, things to interpret lying. Just an idea, and not *that* far fetched.

Re:

[gad_zuki!]

excess heat coming off body

No. They shouldnt be allowed to observe anything a person cant. I cant get up in the middle of a poker game and attempt to stick a thermometer into my opponent's rear to see if he's lying. Why not just put a camera behind him and read his cards? How do you propose we detect sweat? Measuring skin resistance? You cant do that in a real game either.

I think a plain-jane camera would be allowed, but even then its pretty unfair. The human player has no face to look at to potentiall

Limit Holdem

[venicebeach]

Keep in mind these bots play Limit hold'em, where the size of the bets is fixed. No-limit hold'em, the kind you typically see on tv is a much more complex problem - size of bets add more potentially misleading information and more choices to make. (that's why its more exciting to watch than limit)

Re:

[mosch]

There's this myth among new players that no-limit is more exciting. It's so fucking wrong.

The worst part of it, is it's always (always!) spouted by somebody who is so incapable at limit, that they couldn't beat a 20/40 game, let alone any of the high stakes games.

Limit hold'em doesn't televise well because it's hard for an amateur to understand the nuance of what's going on.

Example:
A loose and aggressive button open-raises, and you defend the big blind with ATo. The flop comes down: A82r. You know your o

Re:

[mosch]

Well the main point I was making was about computational complexity.

And I think your point is dead false, especially when it comes to televised poker, in which the blinds are always very large, and the stacks quite short, meaning that the correct move is almost always mathematically provable, if one had the inclination.

If one was allowed, one could sit at the table with software like SNG Analyzer [sitngo-analyzer.com], enter the tournament structure, and assuming the player was capable of making decent estimates of people's rai

Re:

[venicebeach]

I'm not going to argue which is more exciting, since that is up to your personal preferences, although the evidence available to us is that NLHE has achieved a much larger audience than LHE.

About the computational issue you are actually incorrect here, and there is an objective fact of the matter. The reason most poker AI only attempts Heads Up Limit poker at this point is because there are more degrees of freedom in NLHE. At each decision point in a limit match the only options are bet, call, or fold

Real life poker has more factors to it

[eebra82]

The issue I have with this test is that poker is more than just a game of probability, luck and pattern analysis.

If you play on the internet, you rely solely on these three factors, but today's poker celebrities also rely on psyching the opponent and reveal tells. If the bot was capable of emotions as well as reading its opponents emotions, this would be far more interesting.

In the meantime, congress doesn't believe poker is a game of skill.

emergent behavior

[SolusSD]

I wonder how long it would take to teach a large scale neural network to start bluffing. :) When it comes to replicating the complex relationships in our brains neural networks are the way to go.

this isn't man vs machine

[pezpunk]

it's man as the thinkers vs. man as the toolmaker.

until we approach digital sentience that's all we're really doing, isn't it?

Well, in that case...

[Xeth]

I'd like to reaffirm my loyalty for this country and its human president. They may not be perfect but they're the best we've got. For now.

The problem is the software

[biraneto]

The format also eliminated one of the crucial aspects of traditional poker called the tell, subtle clues such as facial ticks that may permit other players to make accurate guesses about the hidden cards held by their opponent. Isn't this like facing world's best soccer player and the computer in a match of Fifa Soccer 2007?

Re:

[meringuoid]

The format also eliminated one of the crucial aspects of traditional poker called the tell, subtle clues such as facial ticks that may permit other players to make accurate guesses about the hidden cards held by their opponent.

Isn't this like facing world's best soccer player and the computer in a match of Fifa Soccer 2007?

Perhaps, but it's hard to say this gives the computer an advantage it wouldn't have anyway. If it's straight man versus machine, the machine only sees cards and bets, so it can't r

Not a surprise: Evolved brains surely better

[wikinerd]

Newsflash: Brains developed over millions of years still outperform computers that have been in development only in the last few centuries. Verdict: Human ingenuity isn't advanced enough to outrun natural evolution (at least not yet), and we still don't know everything about intelligence and computation. Is this a surprise?

Re:

[Ardeaem]

Newsflash: Brains developed over millions of years still outperform computers that have been in development only in the last few centuries. Verdict: Human ingenuity isn't advanced enough to outrun natural evolution (at least not yet), and we still don't know everything about intelligence and computation. Is this a surprise?

We don't know, from the article, how it would do against a sample of average poker players. If it would beat them more than 50% of the time, would you think THAT was a newsflash? Why do you have to question the interest of an article like this just because "we still don't know everything about intelligence and computation." Did anyone say we did?

The computers weren't really playing...

[pscottdv]

Researchers monitored the performance of three bots and then moved them in and out of the lineup like football players

So in a sense the computer wasn't really playing anyhow. I suspect that deciding which bots to move in and out is another skill that humans are better at than computers.

Humans Can Still Out-Bluff Machines

[Angostura]

That's what they want you to think.

Second day was not a fair competition

[dl248]

Look at the first entry (bottom of page) on the Polaris team's blog for the second day. The day that the humans started winning:

http://www.cs.ualberta.ca/~games/poker/man-machine /Live/Day2Session1/ [ualberta.ca]

The U of A team gave the humans the logs of the first two games!

Perhaps after the entire match they could have reviewed the game logs, however this give the humans an unfair advantage during the second day. I can't believe that this isn't getting more attention -- they bascially gave the human team a huge insight into the inner workings, strategy, and tendencies of their opponent. Something that Polaris definitely did not have.

In my opinion this sours the competition and completely invalidates the final two matches. The human likely found a weakness (or two or three) and exploited it, and we can't know for sure that they would have found the weakness without those logs.

That was a huge mistake by the U of A team, and they have apparently got away with it without anyone noticing.

Re:

[Vegeta99]

Why don't you think the computer had logs? I mean, Colin Powell says Iraq has WMDs, but that doesn't make it true!

Yes, I just invoked Godwin's Law Junior.

Randomness doesn't mean hard

[Astarica]

I believe computer can beat humans reliably in backgammon which has an element of randomness in it via dice rolling.

Also, just because the computer won't always win, doesn't mean it isn't better than human. Suppose I made a poker program with X-Ray visions and then played against a random guy. With my X-Ray vision I decided I have a 95% chance to win when the guy went all in, but lost due to a bad draw. Unlike Chess, no matter how good your computer is, there's always a chance you won't win.

When Deep Blu

RTFA

[evanbd]

There were ten "bots"; which bot was in use was controlled by a "coach" program. They actually ran three different programs over the course of the tournament, and that setup actually lost to the humans. The coach / agent approach is an interesting one for a variety of reasons, and it is most definitely a valid strategy.

Re:That's cheating. The computer wasn't playing.

[Anonymous Coward]

Let's see how well the computer does when IT makes all the decisions.

Their answer would be to turn it off and on again.

RTFA.

[raehl]

The researchers didn't choose which bots were used themselves - they had ANOTHER 'coach' bot that moved the 'player' bots in and out.

Re:RTFA.

[bogjobber]

You are also wrong. They chose the bots for the first two games, and the play was very close. They ran the 'coach' bot in the third game, and the computer got beaten "handily".

Re:RTFA.

[CyberLord Seven]

Think of it this way: the human player was playing against a "coach" who could vary his personality through the game.

why so wordy?

[Quadraginta]

/* Design for computer poker player.  Some implementation details missing. */

#include <stdio.h>
#include <poker.h>

int main() {

   printf("Hello, world.  I am a poker-playing robot.  Prepare to lose your shirt.\n") ;

   while (!win_poker_game()) {
      printf("Curses! Another game, human?"\n") ;
   } ;

   printf("Ha ha!\n") ;

   (void)rake_in_chips() ;

   return(0) ;
}