For all you math guys out there

Bruno712

Banned User
Joined
Mar 15, 2004
Location
Boston, MA
What are the chances of this occuring in a clean game of BJ?

Playing single hand BJ, (advertised at 6 decks I believe) playing approximately 100 hands while betting $25/$50 dollars, holding my own then maxing out to $400 and losing 9 straight hands. Not only losing, but losing to either a dealers BJ or a dealer 21. Then doing the same thing the next day and lsoing 6 to a BJ or 21. The next day 7 times (2 pushes) to a BJ or 21.
 
Bruno712 said:
What are the chances of this occuring in a clean game of BJ?

Playing single hand BJ, (advertised at 6 decks I believe) playing approximately 100 hands while betting $25/$50 dollars, holding my own then maxing out to $400 and losing 9 straight hands. Not only losing, but losing to either a dealers BJ or a dealer 21. Then doing the same thing the next day and lsoing 6 to a BJ or 21. The next day 7 times (2 pushes) to a BJ or 21.

Hi Bruno;

What Casino was this?
 
Bruno712 said:
What are the chances of this occuring in a clean game of BJ?

Playing single hand BJ, (advertised at 6 decks I believe) playing approximately 100 hands while betting $25/$50 dollars, holding my own then maxing out to $400 and losing 9 straight hands. Not only losing, but losing to either a dealers BJ or a dealer 21. Then doing the same thing the next day and lsoing 6 to a BJ or 21. The next day 7 times (2 pushes) to a BJ or 21.

I never worry about how I lose just how many times I lose. A loss is a loss is a loss.

And I'm sure you know one can't tell you how bad your session was without knowing the overall results.

I think a dealer will get a BJ or 21 about 12% of the time, if that's any help.

I've never subscribed to the belief that there is a correlation between large bet size and W/L %, if that is your point, but I realize many do. I've often thought, if one believes that, then ... don't make any big bets. Problem solved.
 
Bruno712 said:
What are the chances of this occuring in a clean game of BJ?

Playing single hand BJ, (advertised at 6 decks I believe) playing approximately 100 hands while betting $25/$50 dollars, holding my own then maxing out to $400 and losing 9 straight hands. Not only losing, but losing to either a dealers BJ or a dealer 21. Then doing the same thing the next day and lsoing 6 to a BJ or 21. The next day 7 times (2 pushes) to a BJ or 21.

The probability of 7 dealer BJs or 21s in a row in 100 hands is somewhere about 1 in 20000 or 30000, so you have indeed experienced some rare events, so I don't blame you for being suspicious. On the other hand, if I were to write cheating casino software, I would do it in more subtle ways.
 
I agree Clayman, never max out the bet

According to my logs, the dealer may not have always won, but had 20, 21 or BJ 96% of the time when I maxed out a bet (1109 times in 1156 hands), with the 1156 maxed bets made out of over 35000 hands in total.

Here's another one for you guys, 17 straight losses in video poker betting $25/hand on single mode. That has never happened to me before. Nothing even close.
 
On average, the dealer should get about 20s, 21s and BJs about 350 times out of 1156. The probability of a dealer getting 20, 21 or BJ 1109 times or more out of 1156 hands is in the range of 1 in 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 (that's 500 zeros). Are you sure you got this right? If so, save your logs, print them out, maybe even videotape yourself checking the logs on the computer to prove that you did not manipulate the files. This would be solid quantitative evidence of cheating.

In comparison, 17 losses in VP is quite normal. The exact probability depends on what kind of VP you played. For full pay JoB, the probability is about 1 in 30000, i.e., more likely than a royal flush.
 
Bruno712 said:
According to my logs, the dealer may not have always won, but had 20, 21 or BJ 96% of the time when I maxed out a bet (1109 times in 1156 hands), with the 1156 maxed bets made out of over 35000 hands in total.

Here's another one for you guys, 17 straight losses in video poker betting $25/hand on single mode. That has never happened to me before. Nothing even close.

Which casino did you play at?
 
GrandMaster said:
Are you sure you got this right?

I read it as 1109 over ~35000 hands. Which isn't so bad. If it's over 1156 hands, as you say, they are cheating. No doubt at all. Do you know how many BJ's, 20's 21's over the 35000 hands? That is, I assume you got some on non-max-bets.

I gotta say that percentage of BJ's, 20, & 21's on maxed-out bets is certainly making me wonder, even if the overall percentage to total hands is OK. Certainly the most solid evidence I've ever heard of that bet size effects win rate. My "big bets" have never been max-out bets and, as I've always said, my win rate is OK over every bet size. I really don't know what to say about your experience. But get those logs because it kinda smells, even if over 35000 hands. Smells real bad. Any chance you know how many units you lost on your 1156 maxed-out bets? Sounds like it would likely be next to impossible.

The insidious part is that it would seem to me to be possible to have an overall win rate that would pass all statistical tests by simply forcing wins on big bets and making up for it with more wins on low bets. Which, in a nutshell, is why I record all my hands.

Are your stats from the logs themselves or your own recordings of results of hands? Assume the latter, get the former.

Maybe GM can figure out the chances of having 1109 BJ's, 20's or 21's on 1156 maxed-out bets in 35000 hands. Is that what you are saying? I'm a little blown away right now. By both what I think I'm reading and a few hours at the Elks club. See you tomorrow.
 
What I used

I took my game logs directly from the casinos' records of each hand played, not my chicken scratch.

I did not do the computations personally. I sent them out to a former associate who has a program that analyzes statistical data for poker players but is easily apapted to other games of chance so I can't speak to the accuracy of these figures at this time. According to what he has told me, it will take at least two weeks for a full analysis due to the number of hands that he needs to scan and enter. That is why I refuse to divulge any casino names or make any premature statements. He has only done some preliminary analysis focusing mainly on the $100 and $400 bets and the double downs.

I will also say that I did not check to see if all the logs the casinos have reflect the complete number of my play sessions. When I went to check one of my sessions yesterday, I noticed that it was not there. I know that I must have played over 1000 hands during that session and won over $3000. I am currently out of town and working from my laptop so I cannot cross check this until I return on Monday.

The 17 straight losses were in a 9/6 Jacks or Better single hand game betting $25 per hand ($5/5 lines)
 
Bruno712 said:
I sent them out to a former associate who has a program that analyzes statistical data for poker players but is easily apapted to other games of chance so I can't speak to the accuracy of these figures at this time.

Keep us posted. I hope his program works better than True Gambler's did.

And, I gather, people actually pay for OCA now. Amazing.

If you think I can help in any way, feel free to PM me.
 
Clayman said:
I read it as 1109 over ~35000 hands. Which isn't so bad. If it's over 1156 hands, as you say, they are cheating. No doubt at all. Do you know how many BJ's, 20's 21's over the 35000 hands? That is, I assume you got some on non-max-bets.
1109 over 35000 would be way too low, that's even less likely, if that were true then the game would be rigged in the player's favour. The only way these numbers make sense if 35000 is off by a factor of 10, and the number of hands is only 3500.

The probability of the dealer having 20, 21 or BJ 1109 times out of 3500 hands is tricky to calculate, becuase it is depends very strongly on the exact probability of 20, 21 or BJ, which in turn depends on the number of decks and whether the dealer hist soft 17 or not. Taking the probability of dealer's 20, 21 or BJ to be 0.3, the probability of the dealer having 20, 21 or BJ at least 1109 times out of 3500 is about 0.0144 or 1 in 69. If you change 0.3 to 0.305, the probability increases to 0.0618 or 1 in 16.

Bruno712, can you check the numbers again because they don't seem right to me.
 
GrandMaster said:
1109 over 35000 would be way too low,

Sorry - of course you're right. I wasn't too good at multiplying 35000 by 30% :)

Basically not very much makes very much sense.

I'm sure we'll hear more from Bruno when he gets back to the office next week. Hope so anyway.

Edited to ask

OK lets say there were 10,500 BJ's, 20's & 21's in 35000 hands (30%). Let's say he made 1156 max bets in those 35000 hands and that 1109 of those max bets were against a BJ, 20 or 21. Wouldn't that alone be strong evidence that bet size effects outcome? Even though the traditional units won/lost analysis for the 35000 hands might still appear to be OK? Would you think it likely a casino over a long period of time could get away with rigging only max bets in this fashion?
 
Last edited:
Clarification

Clay,

You are using the 1109 figure as the total number of 20, 21 and black jacks the dealer received out of the 35,000 hands. That is not the total number of those hands. It is the number of those hands the dealer received when I maxed my bet ONLY. I do not have the total amount of ALL 20, 21 and BJs as of yet. I maxed my bet 1156 times. Out of those 1156 hands only, the dealer caught 20, 21 or BJ 1109 times. He, of course, caught those hands on my other wagers, but I haven't received that figure back yet. Another thing I may not have said (or I may have, I'm getting older by the minute here). I did not lose the entire 1109 hands where the dealer caught those hands. I pushed some and won very few.

I hope that clarifys things and gives you more insight about my concern.

Dead Tired In Massachusetts,

Bruno
 
Not without the facts.

Gambolini,

In 1973, to my shock, my name appeared in my hometown (a Boston suburb)newspaper as having been arrested for assualt with a dangerous weapon. Not a real good thing to happen to a pre-law student. The problem was that on the day in question, a Saturday in October, I was running for 115 yards against the U of Miami IN MIAMI!!!!!! Some idiot punk who I grew up with got arrested, presented no ID and used my name and the ignorant cops booked him without verifying his identity. Thus, the erroneous police blotter. Even after the newspapers retraction, I was questioned about and looked down upon for a crime I never commited. So you won't catch me casting aspersion at anyone until all the evidence is in and verified.

I was probably wrong to broach the subject before I had all the answers, but I did. Look at it like a serial, a cliff hanger, LOL. So tune in same Bat time, same Bat channel.
 
Bruno712 said:
Clay I maxed my bet 1156 times. Out of those 1156 hands only, the dealer caught 20, 21 or BJ 1109 times.
Thank you for confirming it. This is conclusive evidence that the software is rigged. You must have lost quite a lot of money. You should have stopped earlier, just 24 out of 25 times (probability 1 in 200000000000) would already make me very suspicious.
 
cont...

Grandmaster,

Indeed i did! From up $3k to down $3K at one casino. But I had just hit a Royal so I wasn't as concerned as I should have been. A real bad habit I have. I habitually break the rule that says "Any money sitting in my account is My money". I continue to justify my playing with "Their money". But I'm aware of it and I'm working on it. My analyst would be proud.
 
GrandMaster said:
Thank you for confirming it. This is conclusive evidence that the software is rigged. You must have lost quite a lot of money. You should have stopped earlier, just 24 out of 25 times (probability 1 in 200000000000) would already make me very suspicious.

Bruno - thanks for the clarification - I think I finally understood it right (see after my "edited to ask" above.)

GM - You are saying that if one randomly picked any 1156 hands from a 35000 hand sample, one would expect about 1156*.3=347 hands that would be a BJ 20 or 21 versus the 1109 Bruno is reporting. This still would be conclusive evidence of being rigged even if the entire 35000 sampled contained the expected number of BJ's 20's or 21's, say 9391 non-max-bet hands. Right? (9391+1109=35000*.3)

What I find interesting, if this is true, is that True Gambler's OCA software might never have found a rigging like this since he never took bet size into account, assuming it to be irrelevant. Correct? Apparently Bruno had a max bet about 3% of the time but I wonder what % of all bets made at a casino are max bets. I'd guess alot less than 1%. And I'd guess it might be a while before anyone would suspect this since typically I doubt if most bankrolls would survive the loss of much more than a few max bets and therefore it would be difficult to get a sample size. I doubt it is something PWC looks at when issuing those silly monthly payback reports. Is it? If they did, the W/L %age on max bets would stick out like an elephant at a dog show. What is your opinion on the feasibility of a casino rigging only max bets in this fashion? A little too obvious?

This whole question of "losing more with bigger bets" is something that has often been complained about over the years and something I have found difficult to disprove conclusively. If this is occurring with one of the major software providers, would it be an exaggeration to say something like this could change the entire landscape of internet gambling?

Bruno - you have the right attitude in saying you may have been wrong in even broaching this before you had all the facts. I think you are aware that you are dealing with TNT here. You also said earlier "I can't speak to the accuracy of these figures at this time". Has that now changed? Is your friend certain of this max-bet analysis? Rest assured, if this is confirmed, many questions will be asked as to his methodology. Will you be ultimately willing to have these logs subjected to other 3rd party analysis? Have you even verified them for completeness yet? I'm curious - were your logs presented to him in a text or database format or as picture files?

I certainly am staying tuned to this Bat-channel!
 
Bruno, would you mind providing some more details about the bets?

You mention that the preliminary analysis looked at the $100 and $400 bets. Is the 1109 of 1156 figure $400 bets only (and all such bets), or does it include $100 bets and others?

Is 1156 determined by a specific bet size (e.g. all bets of $100 or more), or by some other method?

What is the table limit?

Do you use a progression to determine your bet size?

Is the software provider one of the big ones, or a small operation?

TIA.
 
In case you missed the last episode...

Okay, I'll try to be as specific as possible.

Regarding the 1156 maxed out bets in question. They were made on $1/$100 and $25/$400 tables. I do not have a breakdown of the different size max bets ($100 v. $400) although I do know that, although I played on other limit tables, I apparently did not max out any bets on them.

For all you guys that want to think this was done according to some scientific method, allow me to say that this was not done as an experiement. Consider this more Flemming than Jenner, if you catch my drift. It was merely me playing in the course of my daily life. I did not play with the intention of collecting imperical data with which to prove a theory. I was simply playing black jack as I always do (using basic strategy but no specific betting strategy unless you call 'gut' feeling a strategy). It was not until I noticed that I seemed to be getting screwed on my maxed out bets that I became concerned enough to look into this. Then it snowballed. So before anyone mistakes this for the online casino industries Hiroshima, please relax. The legal rammifications of releasing the results of the analysis is being discussed as I type. Remember, it is not only myself involved, but the person who owns the rights to the analyzing program. I will say this, however. If I can trust the hundreds of emails I have received since posting my original thread (Hats off to you, Bryan. You're portal is, apparently, a real popular place, bro), from people a lot higher up on the gambling and legal food chain than you and I, this little observation of mine was not an Epiphany reserved for me alone!
 
Clayman said:
GM - You are saying that if one randomly picked any 1156 hands from a 35000 hand sample, one would expect about 1156*.3=347 hands that would be a BJ 20 or 21 versus the 1109 Bruno is reporting. This still would be conclusive evidence of being rigged even if the entire 35000 sampled contained the expected number of BJ's 20's or 21's, say 9391 non-max-bet hands. Right? (9391+1109=35000*.3) I certainly am staying tuned to this Bat-channel!
The proportion of dealer 20's, 21's and BJ's should be around 30% in any sample which is chosen in a way that's not correlated to the outcome. You could choose 1109 hands at random, or the first 1109 hands, or the hands where you bet the table max. Choosing the hands you lost would not be OK, because you expect more dealer 20's, 21's and BJ's in your losing hands (but my gut feeling is that 96% is still way too high for a sample of this size).

If the overall proportion of dealer 20's, 21's and BJ's is OK, but it is too high or too low in the sample, then my conclusion would be that the sample was not chosen in a random way, somehow it is correlated to the outcome.
 
My take on it

I hear what you're saying GM. But it is my contention that if the remaining 34000 (35000 - 1150 or so) or so hands where the max bet is not made contain 30% 20, 21 and BJs for the dealer, it is the max bets ONLY that are the aberation. Maybe I am starting with a presupposed conclusion and making the figures confirm it, but it would still be extremely odd to have that aberation show its face exclusively on the maxed out bets. And I believe that is what Kyle is doing. He is taking random samples of all hands when comparing it to the maxed out bets. In other words, he would take a few samplings of any given 5000 hands, max or min bet, and see what the percentage of dealer high hands are. High hands being 20, 21, BJ.

Speaking of aberations...

I just hit a full house, 4oak, full house, full house and 3oak in a row at Brandy in JoB, single mode.
 
I have not seen the data, but there are all sorts of things you can do, there are statistical tests you can carry out to see whether the software is rigged at all levels or only at maximum bets.

I have a question. What happened if you busted? Unless you are playing at a multi-player table, in most software versions the dealer won't play out his hand if you bust, so you won't know what would have happened. How were these hands recorded? If the dealer doesn't always play out his hand, counting dealer 20's, 21's and BJ's is probably not the best thing, but I don't think it is a big problem. My gut feeling is that the dealer is slightly more likely to have a high hand when you bust, because more than 1/3 of all high hands come from the dealer showing a 10 or a face card, and ending up with 20, and you have to play more aggressively when the dealer is showing a 10, so you are more likely to bust. This means that probability of dealer high hands when you don't bust is actually slightly less than 30%.

I would look at other things, overall win/loss/push ratio, win/loss/push ratio at each betting level.

You should check out winneronline.com, search for ohdreampop in the forum. She got a 20k royal at Brandy casino on her first hand after getting the sign-up bonus.
 
So, is this the first time you play in this casino? If not, has it always been like this? tell us the name to stay away from them
 

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