Mathematical Proof that English Harbour is cheating

**thelawnet** · 29th April 2006, 10:46 AM

Originally Posted by jsp377

My post has been replaced and edited due to not thinking on my part.

liquidsoap is absolutely right that just because the probability is low, that does not mean the game is rigged. If it DID mean the game were rigged, than any small number of hands in video poker that yielded an RSF would be considered to be rigged in favor of the player.

What makes this binomial distribution different from that is the Central Limit Theorem. By the time you've got a 235-sample binomial, that makes a pretty frickin' good approximation of the normal distribution. Therefore, we can judge the likelihood of getting only 84 wins with a normal distribution of mean mu =.5*235=117.5, and standard deviation sigma=sqrt(235*.5*.5)=7.665. Now, 84 wins is (117.5-84)/7.665 = 4.3706 standard deviations away from the mean. This has a probability of .0000062, even LOWER than that suggested by the original poster. In fact, despite using a binomial distribution, his analysis was basically spot on.

Actually my analysis was spot on, it was not basically spot on.

The binomial distribution is the distribution of n trials of a 2-valued event with probability p.

The result you have used is the normal approximation to the binomial distribution. The only reason to use the normal distribution for this is if it is inconvenient to use the binomial distribution (which it is not if Excel calculates it for you). The binomial distribution is exact.

As you say, it does not make much difference, but the binomial distribution is the better one to use here.

**thelawnet** · 29th April 2006, 10:52 AM

Originally Posted by Aindreas_Daoc

Out of curiosity I tried this just now, using play money mode, doubling 1 line tens or better.

My results: 25 W, 65 L, 10 T. 100 tries total.

In my opinion, this is not a fair doubling game. Someone ought to contact Michael Shackleford (Wizard of Odds) and get his opinion.

Thank you for your results. Providing you just took the first 100 tries and did not wait for a bad run, then treating this as a single sample, the chance they are cheating is:

99.999999998%

That is, approx 50 billion to one, such that you would expect to get such bad results in 18 trillion doubles

That is even more absolutely conclusive that they are cheating.

**sk2005** · 29th April 2006, 01:49 PM

Originally Posted by liquidsoap

Fixed
You need to add about 100,000 more hands if that to find out if it is fixed....

Just another loser with a conspiracy theory....
When you hit the royal flush, complain to them thats its fixed

I am waiting for the day when some idiot will come to this forum with 100.000 hands statistics and with about one millon dollars lost. And he will prove finally that some casinos may be rigged. There is no other way to prove it (unfortunately). And until that time we must believe the online casinos are absolutely fair

**bpb** · 29th April 2006, 03:41 PM

Originally Posted by liquidsoap

Fixed
You need to add about 100,000 more hands if that to find out if it is fixed....

Why would you post such an absurd statement?

**Aindreas_Daoc** · 29th April 2006, 04:56 PM

Originally Posted by thelawnet

Thank you for your results. Providing you just took the first 100 tries and did not wait for a bad run, then treating this as a single sample, the chance they are cheating is:

99.999999998%

That is, approx 50 billion to one, such that you would expect to get such bad results in 18 trillion doubles

That is even more absolutely conclusive that they are cheating.

Yes, those are the first and only 100 tries I did last night.

**Aindreas_Daoc** · 29th April 2006, 05:02 PM

Originally Posted by Zoozie

Actually my worst doubling experince also happened at English Harbour(Oddson software). I was playing doubling in the 5$-10$ range (bet size could matter).
I lost like 23 or 24 out of 25 doubles and then I busted. However this small sample size says nothing. After this happened I stopped doubling (at all casinos).

I once made a test like you did at Playtech with a larger sample size and the
results showed a fair game. (Actually I had a little more wins than looses)

However my point is, where does it say that doubling has to be a fair game at online casinos?

Because at BEST you get a fair game, but there is no garantie. There are strict rules that VP games/Dices has to be fair, but are there similar rules for doubling?

Zoozie

In any land based casino in the US, a game displaying graphical representation of cards has to behave as if the cards are real, ie. fair game. Of course online a casino can do whatever they want, but that doesn't make it right. Things like these just gives the anti-internet gambling lobby more ammunition.

**soflat** · 29th April 2006, 05:56 PM

100 doubles on the flash version play money mode:

40 wins
55 losses
5 ties

**Linus** · 29th April 2006, 06:41 PM

However my point is, where does it say that doubling has to be a fair game at online casinos?

You're kidding, right?

Net/Doac, would you mind explaining what you're doing with the binomial-whatevers in English, plz?

Thanks.

Edit: I do understand normal distributions/bell curves, and standard deviations (more or less) if that helps.

**gfkostas** · 29th April 2006, 06:52 PM

Originally Posted by sk2005

I am waiting for the day when some idiot will come to this forum with 100.000 hands statistics and with about one millon dollars lost. And he will prove finally that some casinos may be rigged. There is no other way to prove it (unfortunately). And until that time we must believe the online casinos are absolutely fair

Well said, I hear you

**CROGO** · 29th April 2006, 07:14 PM

I don�t doubt the results or the conclusion, but if this is intentional, then they will fix the free play software so that is truly random, and leave the real money software alone. So in that way, you wouldn�t be able to �clock� the RNG before playing for real money.

This is all the more reason to only play at sites that are audited by some legitimate third party.