Poker Driving Artificial Intelligence Research

J-Hawker writes "The Canadian Press has a story about a University of Alberta team that is using Texas Hold-'em to study artificial intelligence. Poker seems to be a much more useful game for this research than chess. From the article: 'Poker has what are currently some of the biggest challenges to (artificial intelligence) systems, and uncertainty is the primary hurdle that we're facing,' said Michael Bowling, adding that the University of Alberta program was able to use its opponents' actions to infer certain things about their hands. 'The same techniques, the same principles that we're developing to build poker systems are the same principles that can be applied to many other problems. The nice thing about chess as a property of the game is what we call perfect information. You look at the board, you know where all the pieces are, you know whose turn it is — you have complete knowledge of the game,' he said. 'But in the real world, knowing everything is just so rare. Everything we do all day long is all about partial information. So poker's much more representative of what the real world's like, and in that sense it becomes a much harder problem.'"

Comments

Straight Forward Evaluation

[eldavojohn]

Poker seems to be a much more useful game for this research than chess.

This shouldn't be a surprise. Poker has the advantage of always being able to simply evaluate your chip count. Chess doesn't. You can't enumerate chess games through the entire gamespace so the initial opening moves are based on libraries or heuristics. In response to the machine not knowing all aspects of the "game space," I thought that there were a lot of developments in the field that allowed these to be accounted for. What ever happened to good old Trial and Error or Fuzzy Systems? Aren't these viable strategies when playing poker?

What confuses me is how the poker openings differ. I would speculate that a program would be some heuristic relating the ratio of bluffing to "playing the odds." I have gambling friends that play poker all the time and they have these rules that they follow when they play initially against people. They say it's the best until you "know" the people you're playing. Once you can read them then you deviate from the rules. The real irony is that the most successful people I know adhere to a system until they learn someone's movements. Sounds to me like I would write an application that specializes in playing the odds until it recognizes a historical action that statistically reveals the player is bluffing/not bluffing.

Simply put, unless you knew someone's reputation as being a bluffer, you would play the opening hand always the same way. Aren't we forced to program the "AI" of the poker software as being this simple heuristic? Will programs ever be able to "read" players intelligently or will they rely on Markov models & statistics they develop from playing against the same human over and over?

Most unfortunate is the fact that the primary reason my friends gamble is they don't experience the same kind of rush while playing other games as they do with poker because it's more social than other games. If we program applications to beat humans, where does the "social aspect" of the game go?

Even more interesting is the network of poker bots that are set up and running some of the web sites that host poker players. Imagine sitting down at a table of five with four of the other seats taken. Now imagine that these aren't humans but instead bots on four different IP addresses that are sharing card information over an IP connection so that they can leverage odds over you and stop themselves from making stupid mistakes (i.e. they share a card on the table for a pair but really need three of a kind to pose a threat). There's a reason why the percentages fluctuate on TV when cards are revealed whether they be in the flop or in another player's hand.

Re:Straight Forward Evaluation

[bdonalds]

Now imagine that these aren't humans but instead bots on four different IP addresses that are sharing card information over an IP connection so that they can leverage odds over you and stop themselves from making stupid mistakes

Just to address a small part of your post- Bots Schmots! This is a problem already with humans. I used to like to play Euchre and the like online, but too many times it became obvious my opponents were communicating to each other and ruined the fun.

Re:Straight Forward Evaluation

[Pulzar]

I used to like to play Euchre and the like online, but too many times it became obvious my opponents were communicating to each other and ruined the fun.

In Euchre, knowing your partner's cards is a *huge* advantage... In poker, knowing the cards on one other player at the table gives you such a minute advantage that it's irrelevant in almost all practical cases.

Sure, if all of the players at the table except for you are sharing their cards, and are not required to conceal it (i.e. they can openly collude in their betting patterns against you), then they have a big advantage. But, that's, again, not very realistic.

Re:Straight Forward Evaluation

[Propagandhi]

Aren't we forced to program the "AI" of the poker software as being this simple heuristic? Will programs ever be able to "read" players intelligently or will they rely on Markov models & statistics they develop from playing against the same human over and over?

Playing poker with 100% consistency is no way to be an excellent poker player. It's easy to make a bot that follows a set of statistics which give it a good chance to win regardless of how their opponent ha played in the past, but if the bot takes into account the player's past actions then it can improve its chances of success. Taking into account the opponent's aggressiveness becomes especially important late in a tournament style match (when other players have been eliminated), most bots aren't designed to play in these situations (hence why you don't see many bots in tournaments, playing instead at the normal tables).

The bot would, ideally, be as good as a very observant player, noting those who bluff and those who don't. Obviously noting 1 or 2 bluffs or non-bluffs would not be enough to make a decision, but over the course of a long tournament, or even better a poker playing career, this information would become very useful. The bot would learn its opponents, and this is what makes it an interesting problem.

Even more interesting is the network of poker bots that are set up and running some of the web sites that host poker players.

I'd argue that cheating at online poker isn't very interesting at all. Humans can do the exact same thing, and online poker companies monitor game's to ensure that there isn't an uncommonly high percentage of people in the same area playing any game. Obviously it might be easier to distribute the bots across the country, but I think it's still more likely (today) to run into actual players grifting you in this manner.

There's a reason why the percentages fluctuate on TV when cards are revealed whether they be in the flop or in another player's hand.

Quantum physics, right? You can accurately determine the odds of winning, or the cards in hand, but not both at the same time? Swear I read something about this somewhere.

Re:Straight Forward Evaluation

[brunes69]

What confuses me is how the poker openings differ. I would speculate that a program would be some heuristic relating the ratio of bluffing to "playing the odds." I have gambling friends that play poker all the time and they have these rules that they follow when they play initially against people. They say it's the best until you "know" the people you're playing. Once you can read them then you deviate from the rules. The real irony is that the most successful people I know adhere to a system until they learn someone's movements. Sounds to me like I would write an application that specializes in playing the odds until it recognizes a historical action that statistically reveals the player is bluffing/not bluffing.

You can tell you don't play much poker.

Part of what differentiates a pro player to an amatur player in poker, is the ability to "project an image". A pro player will purposefully *project* an image of a bluffer, or a tight player, so that they can exploit that image of themselves when they see fit in the game.

Thusly, it is very difficlt to get a "read" on a good poker player, because not only do you not know what cards they have, but you don't know how they would play for any two given cards, so you can't use their behaviour to prdict the cards they have.

In the end, the above description is what any decent player is aiming for while they play.

Because of this, a computer can have a hard time going beyond implied odds calulations in determining how to play a hand - and any pro ill tell you, implied odds are a good starting point, but they won't make you money in the long run.

Re:Straight Forward Evaluation

[rcs1000]

Two things:

(1) Knowing the cards of the other players is a small, but significant, advantage. Say you've got two hearts, and your three buddies have a heart each. Well, you're chance of getting another three hearts on the table are significantly affected. (Likewise, if they have none, it increases the chance you'll want to stay in and catch the flop.)

(2) Much more serious, though, is collusion in betting. You and your buddy can conspire to raise the pot *as much as you like*. In a fixed raise game, this is an enormous advantage. Another player cannot just "call" and see the next card, as there will always be a player still to call who can reraise.

Personally, though, I love bots. I'm happy to play them all day long. (So long as they're not colluding, of course...)

Cheers,

Robert

AI doesn't work for Spades!

[Dareth]

The AI is "able to use its opponents' actions to infer certain things about their hands"

While it may seem logical to use the actions of people playing to determine something about their hands, in reality people do not play logically. My uncle has been playing spades for probably better than 30 years, yet I have yet in my relatively limited 10+ years of playing to determine any rational for how he plays. Basically, he really sucks at spades. No matter how "Intelligent" artifical or otherwise I manage to code a game, it can't reason out the reasoning behind a non-logical person.

Good quote I say somewhere: Artifical intelligence is no match for natural stupidity!

And this holds true for more than card game AI. It will not be too long until AI could reasonably drive around and get from point A to point B safely. But it will be a damn long time before it can do it if it has to share the road with people driving as well!

Re:AI doesn't work for Spades!

[Relic of the Future]

Go play against any of the simple online paper-scissors-rocks bots; then come back and re-evaluate your position.

You are not as unpredictable as you think.

More info than a real player?

[Red Flayer]

To ensure that no one computer got lucky, each side was given the opportunity to play its opponent's hand after each deal.

Thereby eliminating one important premise of poker -- you don't know what hand an opponent was playing unless someone called the last bet. In terms of an algorhithm for the program to 'learn' based upon others' behavior, this means the program has a lot more information than a regular player would. Of course, it's possible to verify that this info isn't fed into the algorithm, but I'd be more impressed if the info wasn't available at all.

Also, why ensure that no one computer got lucky? Isn't that the point of playing several thousand hands of limit poker, to eliminate the effect of luck in the study? If it's necessary to normalize all the hands received by the players, then something else is wrong with the study. I'd like to see if the results differed, and how, when the hand repetition is removed.

Not anytime soon.

[Lejade]

Before anyone goes off about how AIs will eventually replace us, my company runs a (GPL and GNU/linux friendly) poker site and the last thing i am worried about is bots taking over humans in no-limit games. To win consistently against serious players an AI would need to be a LOT smarter than what the guys from Alberta have. It would need to have a serious grasp of human psychology. It might happen, eventually, but by then society might have changed so much that "money" might also be an obsolete concept...

And even if such software existed, it would basically mean that you couldn't win at online poker anymore because skill would not be relevant anymore. That wouldn't be very different from the current situation with player-versus-casino luck games (like roulette or slots).
And we can all see how poorly these are doing, right? :)

Re:Bluffing

[Cherita Chen]

Most good players don't actually "Bluff" in the sense that they are totally full of crap, and have no hand. Most bluffs are calculated risks based on the overall odds of "Improving" the hand, such as the case with four of a suit and two cards left to be turned over. In that case, the overall odds of hitting the flush are good enough to bet on (unless of course there is a pair showing on the board, which would indicate a possible full-house), even though the player has no "real" hand yet. Situations such as this can be quantified. Granted there are some real morons out there who will try to "bluff" with nothing, they are relatively rare and don't usually last long.

Already bots playing

[slapyslapslap]

There are already bots playing against unsuspecting people at the online casinos. I'm not sure how much AI is involved, but apparently they play better than most humans.

Re:Bluffing

[AuMatar]

Good poker players constantly semi-bluff and do continuation bets. They do plain bluffs in some situations too. Its all about reading your opponent- if I think an opponent will lay down a hand if he doesn't have a pair, I will always bet on the flop even with nothing- the odds favor him having nothing as well, and if he always lays down non-pairs I'll win more money by betting than I lose.

Re:If you are really interested...

[Best ID Ever!]

If someone had a bot that could successfully beat online poker, why would they sell it?

stupid computer

[ExE122]

"Computers aren't particularly good at learning, for example, or reasoning by analogy"

Computers aren't good at retaining knowledge and recognizing patterns? That's news to me... this statement is obviously made by someone who doesn't know what he's talking about...

A very strong and useful technique in AI is to create learning algorithms. Some of these, such as reinforcement learning, are actually quite effective. Using something like Monte Carlo methods to give it a randomness factor simulates human learning, and computers don't forget what they are taught. The difficulty with learning isn't that computers can't do it... it's being able to define an effective set of state-action pairs for the computer to learn upon.

I spent time researching natural language processing, sometimes using AI techniques that did exactly what this person claims computers aren't good at: reasoning by analogy. One method involved building a knowledge base which generalized input so that patterns can be found and the grammar could be recovered. The weakness in the system wasn't reasoning by analogy, in fact I'd say computers are much better at that than people. It was rather a lack of a real world model which allowed for a wider array of perception.

The reason this game is difficult is not based on a computer's inability to solve problems, rather that there are so many possibilities that we cannot effectively design algorithms that the can be put to use. This isn't even news, the same has been said about the game of Go for the longest time.

I think a more accurate statement for this person to make would've been: "The overwhelming complexity of poker makes it a difficult game to define in a way for a computer to be able to play effectively."

--
"A man is asked if he is wise or not. He replies that he is otherwise" ~Mao Zedong

Computer Go

[dahl_ag]

While it probably doesn't have nearly the financial motivation that poker does, the AI behind Computer Go also represents a huge challenge. The rules of Go are very simple, but it is impossible to 'solve' using brute-force techniques like you might use with something like chess.