Online poker cheating

One of the projects I’ve been engaged in lately is trying to catch players who are cheating in online poker.

(This is unrelated to the Pokernomics analysis I have also been doing — although at a glacial pace. For those of you who sent me hand histories we will be getting you ring game analyses within the next couple weeks.)

It turned out to be harder than I thought it would to catch online poker cheats. I have found lots of behavior that looks awfully suspicious in the data, but it doesn’t seem like the players do much better when they are behaving suspiciously than when they are not. So far, I can’t figure out whether what looks suspicious to me is not cheating, or whether cheating of the sort I’m looking at doesn’t provide a player much of an edge.

Recently, some highly regarded young players got caught playing under multiple identities in the same tournament. (See here and here, although if you aren’t a poker insider the posts are a little confusing). Thanks to Scott Cunningham for pointing me to these two links.

Because of these two projects on poker, I figured I better play a little myself to understand the game better. I was surprised how much fun it was. I was a big loser initially, even in low stakes games. Now I’m still a loser, but not as much, and at much higher stakes. I’ve even had the honor (??) of losing to the guys who just got caught cheating.

But the best news is that my wife Jeannette quickly picked up the game and now does not consider her day complete if she can’t slip in a few sit-n-go no limit hold ’em tournaments after the kids go to sleep. I married well.


Oh, and for those that have played online poker, what mechanisms do they have to protect from these simple schemes? Or do they merely shrug and say, buyer beware?


Dear Freak,

A couple things. First, I am a fairly high level ametuer poker player making a comfortable five figure second income. Second, by chance I have an uncle who has been a professional gambler for 45 years. Third, by happenstance, I know a lot of college age online poker players. Fourth, I have a cursory knowledge of stats by virtue of an economics b.a. and being in finance.

Regarding the posts above, pretty basic stuff postulated, I'll give you something more dramatic below. Of course there is a lot of collusion. College kids all over the country and in England in particular and the Far East are playing with different buddies within a group of 20 or more players regularly. Often in the same dorm, apartment or union. They have their own laptop computers, they use school computers, their friends computers, they use various internet connections, including coffee shop internet connections, school connections, open networks, air cards, etc... and they sign up with a different name and payment method with each computer... I know this to be so, because I was invited to join two groups, one out of Wisconsin (that's right, Wisconsin) and one out of Chicago. Luckily, most of those players suck. Not so luckily, there is another reason they don't completely clean up.

The most important cheating is not what you'd think it was, but what you fear it is. The sites are clearly cheating. The only question I have now is it to stimulate rake, or are they taking gambling winnings? Here's a simple study for you. Look up a 100 non-professional big winners using PokerDB or Officialpokerrankings, then use server information if possible to reconstruct hands over a period of several months for those players. See how many times they win, when not a favorite. My uncle and I have logged thousands of hands, and at least at every site that we play, the draw outs are not statistically within the appropriate range for the samples. Either, the sites are letting weaker players stay in the game to stimulate rake or certain players know what is coming in the form of cards. If certain players know what is coming, then the question becomes, why? Are they being told, i.e. the sites and them have a deal, or have they figured something out. I have my guess. You figure it out from here. I know I pointed you in the right direction.



I contacted Full Tilt Poker about Sharkscope showing their results because it runs totally against their site rules in a couple places. They never got back to me. So if you think the sites might be cheating, they might be doing a lot of things. Remember, the DOJ can't touch them, nor can any legal process from America. They're all offshore. Than theoretically, can do anything they want. I play normally just head up Sng's and I would testify that they cook up hands and move the short stacks out quicker.


In reading all the comments above no one has mentioned the most obvious and most likely method that sites have of cheating: what I call phantom players, players that don't actually exist physically but are computer stimulated. These are the most likely winners of the major tournaments prize moneys. They would be impossible to detect and their names could be changed daily, hourly or by the minute; meanwhile all that entrant's money and re-buy money spent would stay right where it is in the site's pockets. Big payouts? Dreams in the sky.


I'm not saying I multiple Account, but FT has definitely made it impossible to get rakeback on existing accounts. If you want to make another account, you should read this article on multiple accounting: . I agree with some of the principles, like DONT TRANSFER MONEY BETWEEN YOUR ACCOUNTS. I never play two accounts at the same table/tournament. Multiple accounts have brought me both profit and trouble. It's a shame that it's prosecuted, but I guess I understand why the sites are coming down on it.


I am not surprised at all, cheating has been around since poker got out. Heres an article about the Ultimate bet poker scandle. It tells the story of potripper on ultimate bet seeing his oponents cards and therefore winning a high stakes poker tourny because of an inside job.

david webber

it is obvious to anyone that knows anything at all that if you can't watch the shuffling and dealing and also handle the cards before the game starts , that you have no game that you are a part of. these online dolts couldn't win a game where they get to deal the cards theirselves is obvious to me,they have no clue to what a real card game is and that is why they can't play it with any chance of success.


Hey Freak, do you want to bust the next poker cheating scandal. It's pretty simple. It's exactly the same as the one at Absolute Poker and Ultimate Bet, except on smaller games. The sites or insiders have absitively, posilutely moved to the smaller tournies and lower limit cash games with their knowledge of hole cards. They are much more savvy in how they play, making sure they lose here and there, and changing IDs frequently. They are pulling in tens of thousands of dollars a week on the cash tables by playing dozens of tables at a time using several IDs, and they are playing in the midsize tournies, i.e. $11 buy in $30k guarantee at PokerStars (I garoooontee that PS is having a problem or is scheming).

Let Barney Frank know that simply taxing internet gambling won't work. It has to be subject to some sort of gaming authority. Sites that don't allow oversight should be banned. The cheaters will move offshore (the ones that aren't already) and won't get taxed anyway, as they are winning a lot of the money.


terry obrien

wow online poker is way more rigged now
the sites themselves are cheating massively

email me - i have great hand histories from carbon poker

they flop 3 suited 1 in 10 these days etc etc (not 1 in 20 as expected)

it is juiced to addict people and rigged to steal all their money


The online poker cheating is the biggest thing in the game. This is because of the poker players and not in the game. Many will do many kind of hacking, duplicate id entries, etc.

cc podcast (sorry)


[...] One rogue economist tackles attempts poker. You’d think that poker would be on most Econ 101 syllabi. [...]


This is a problem I have thought about a lot as well. Part of the difficulty comes from the various ways in which poker cheating can happen. Some cheats might display themselves through their play (e.g., squeezing a victim by re-raising each other until the victim folds his hand fearing the nuts, then one cheater making a suspicious fold on a later street to avoid having to reveal the deception at showdown) vs. completely invisible cheating (e.g., sharing of hole card information, which in a game like Omaha, creates a real edge).

My feeling is that it will be hard to create a diagnostic test that identifies cheaters, because some cheaters will not behave suspiciously (e.g. type 2 cheaters), while many monkeys who play online will appear to be type 1 cheaters when in fact they are simply idiots. Thus the dual problem of being both overinclusive (false positive) and underinclusive (false negative).

I think a more interesting approach would simply be to create a dB measuring the statistical likelihood that a given combination of players is seated at the same table together. The more frequently the players are seated at the same table, the more likely it is that they are cheaters. This would be particularly true in lower limit games where the sheer number of tables would likely mean that even full-time online pros are rarely seated together with great frequency. However as you climbed the limits, and the player pool shrank, this method would work much less well--think, Chau Giang, Doyle Brunson, Jen Harmon, etc. in the big Bellagio game. They play together at the same table with near 100% correlation, but obviously, they arent cheating.

Anyhow, setting aside these situations, where the pool of players/available tables is large enough, it should be possible to create a distribution of "likelihood" that Player X has of being at the same table with Player Y. Look principally for the players whose correlation is several standard deviations off the norm, and you have a pretty good set of "possible cheaters."

The next step would be to figure out if you can slice this subgroup further.


scott cunningham

The way in which these cheaters were caught highlights the challenges of catching them. For instance, Party Poker only caught these guys because others reported them. The first guy, JJProdigy, was in a big multi-table tournament (MTT) playing with two accounts. When his highly ranked "JJProdigy" account got knocked out, his second unknown account one, and he seemed to want the notoriety of winning a large field MTT, so he told some people it was actually him. One of them told someone who told someone who told Party, who only then took action against him. A similar thing happened against ZeeJustin. That they were kids might explain why they couldn't keep it quiet.

But the ability to catch cheaters doing this is very hard, as Party can only go by whether the same computer is on the same tournament at the same time. And it's not too difficult to get around that, if you don't mind investing in multiple IP addresses, computers, etc. Many professional players are quite cynical about online poker, saying that the cheating is so pervasive that it's no longer profitable.


scott cunningham

Derek - that type of test would only work when a player controls the table he sits at, such as ring games. In a MTT, a player can't control where he sits. I'd be interesting in knowing, though, how much of a change in EV occurs when a person increases the number of accounts he's operating in that MTT. What's the likelihood that a person playing 3 accounts will end up at the same table at some point in a 200-person touranment? What's the change in EV with each additional account?


There will never be a great professional economist poker player. Any economist who can master the game would have dropped out of their Ph.D. program way before candidacy...or would have been weeded out in jr. high as they made their fortune and avoided grad school poverty...

tim in tampa

Chris Ferguson is one of the only individuals who really comes from an academic background suited (no pun intended) to poker analysis who has been a major champion. I always believed that those of us who work with this sort of thing ought to be able to dominate poker -- but it's not really working out that way. In fact, I've found I play better on pure instinct than when I use statistics and game theory. That having been said, David Sklansky made quite a career both as a player and writer using almost a purely statistical approach.

I'm not finished working through this, especially considering my dissertation-in-progress is ON poker, but so far, the results have been far from my expectations.



Cheating in MTTs is harder to detect, Im sure, than ring games, but I dont play them, so I could care less. That said, your question about the actual +EV edge from multiple buyins in MTTs is a good one. Let's begin by saying that there is some structural edge for sure, b/c it reduces the volatility of results for the player by creating multiple chances. As you know, you can't win a tourney w/out winning some coin flips (e.g., AK vs. QQ), so simply having the ability to have multiple entries helps b/c the arbitrariness of the coinflips gets spread over a large sample, thus you get a "second chance" (in a different account) when other players would be eliminated. Second chance = lower volatility of results.

As for the EV edge itself, since ab initio everybody's buyin is equal, the skilled players will be able to multiply their natural edge, while the average or weaker players will magnify their disadvantage. In other words, if you're dead money coming in, doubling your buyin will just increase the amount of dead money at stake. OTOH, if you have a +EV skill edge b/c you're Phil Hellmuth, you multiply your edge by doubling the amount of money at risk. This is what Mason Malmuth would basically call a non-self weighting strategy, which is key to all gambles with +EV outcomes.

Beyond the ability to increase your bet when you have an edge, there is the +EV component from cheating tactics themselves. In order to exploit this edge, you need to be seated at the same table as one of your alter identities. This fact alone is impossible to manipulate in the big MTTs. But lets say luck gets you seated at the same table as your alter egos. What is your edge here?

Im not a tourney player, but I would expect that there is some edge. Hypothetically, lets say Identity 1 and Identity 2 got seated at the same table during the random draw of the MTT. You'd have 20% of the chips in play at that table, vs. every other player who would have only 10% individually. Question: does having a chip advantage create a greater +EV edge that is disproportionate to the money required to buy those chips?

I hypothesize yes. Again, Im not a tourney player, but you would have a few moves clearly available only to you. For example: (1) chip dumping to become the big stack so you can attack small stacks and threaten them with elimination; (2) additional hole card information; (3) re-bluff stealing.

By and large, I dont think the strict "cheating" aspects of the multi-identity cheaters is that big. I really think they get an advantage from the structural edges I first mentioned (i.e., do-agains on coin flips, and non-selfweighting bets thru multiple entries).

The fact that ZeeJustin was able to make the final table in an MTT with multiple accounts was quite impressive, and really, is more of a testament to his skill as a player. For guys like him, who are strong tourney players, I think the edge is quite real. (Although if I were a good tourney player like him, I'd cheat not in MTTs but in the large buy-in SNGs. Having two entries on a $500+$50 would be quite advantageous.)


scott cunningham

Derek - Great thoughts. To your last paragraph, it's interesting you say you would've cheated at more large buy-in SNGs over MTTs, as ZeeJustin had the reputation of being an excellent MTT and large buy-in SNG player. He played 10 SNGs simultaneously routinely (not uncommon, and part of how young players gain so much experience in a relatively short period of time), and would exploit such gains routlinely by having multiple accounts at the same large buy-in SNG. (Just rehearsing this again makes me shudder and never want to play online).



I said I'd focus on SNGs instead of MTTs if I were a cheater, simply because I think you're likely to get more consistent, +EV results this way. (Maybe I say this because I can actually win SNGs, but I've only cashed once in an MTT.) Really, if I were cheating, I'd focus on the cash games, however. Multiple accounts playing pot limit Omaha would make you unbeatable.