Is PartyPoker rigged?

D

dacium

Well-Known Member
#1
#1
Firstly let me just say I have never believed the crap about online games being rigged. I have suffered the huge down swings and up swings, however I have never experienced anything as bad as this.

My friend and I just had an insane loosing streak on party poker multi blackjack. we lost about $1000 in 3500 hands playing basic strategy flat betting $1. It started out as loosing $100 in about 300 hands, and we continued on and on and our rate of loosing never improved. The dealer seemed to have a huge run of getting 10 cards up and never getting 6's. This also resulted it huge amounts of blackjacks.

In total we played 3513 hands (which party poker makes you view one per page per hand and only stores upto 500 and only for 3 days).

I had to write a c program and combined with perl scripts I am extracting all the hand history. Here is the dealer up cards:
Code: 
2  234
3  177
4  128
5  323
6  178
7  261
8  323
9  321
T  355
J  291
Q 332
K 305
A 285
Out of 3513 hands the expected value was 249.4.
The standard deviation is 15.79

Obviously there are huge problems here.
4's occured just 128 times, thats 7.68 standard deviations from expected!

The average up card is 4 standard deviations away from expected value! The chance that this combination was drawn randomly is therefore about 4 deviations (99.99366575163%), which is 1 in 15,787!

Party-poker is probably the place I would never expect to be rigged but it has totally lost my confidence.

I am using a perl script to sort the results and I am trying to get the results of double downs won/lost and the ratio of blackjacks for player to dealer also.
 
moo321

moo321

Well-Known Member
#2
#2
I've had 3 SD losses at places that I don't consider to be rigged. I've also had 3 SD wins at places I don't consider to be rigged. I'd say it's pretty doubtful that it's rigged. Too many people playing on there.
 
A

aka23

Well-Known Member
#3
#3
Losing $1000 over 3500 $1 hands is about 15 standard deviations below the mean. You said you played "multi-blackjack." Were you playing single-hand or multi-hand? Many people have played Party Blackjack and have had results near normal expectations. I've never heard of anything like a 15 standard deviation loss before. However, the play does sometimes feel unnatural, more so than other softwares.

Party is a publicly traded company, so it seems unlikely that they would put so much at risk by making an obviously rigged game. If you still have the full hand history, I'd recommend contacting both Party and Wizard of Odds with your results. Party may give an explanation for the results, if contacted. And Wizard of Odds has a good amount of experience analyzing such results. His findings are highly respected by the gambling community.
 
Last edited:
A

aka23

Well-Known Member
#5
#5
dacium said:
Out of 3513 hands the expected value was 249.4.
The standard deviation is 15.79
Click to expand...
Isn't variance 249.4, rather than expected value? Unless I'm missing something:

Mean (expected value) = 3513/13 = 270.2
Variance = 3513*(1/13)*(12/13) = 249.4
Standard Deviation = SQRT(variance) = 15.79
 
Last edited:
KenSmith

KenSmith

Administrator
Staff member
#7
#7
I used a Chi-Square calculator here:
http://www.physics.csbsju.edu/stats/chi-square.html

I plugged in the expected value for each dealer upcard (270, since this calculator doesn't allow decimal places), and the actual values from the initial post in this thread.

The results:
---------------------
13 data/expectation pairs (x,E):
( 234. , 270.0 ); ( 177. , 270.0 ); ( 128. , 270.0 ); ( 323. , 270.0 ); ( 178. , 270.0 ); ( 261. , 270.0 ); ( 323. , 270.0 ); ( 321. , 270.0 ); ( 355. , 270.0 ); ( 291. , 270.0 ); ( 332. , 270.0 ); ( 395. , 270.0 ); ( 285. , 270.0 );
chi-square = 275.
degrees of freedom = 12
probability = 0.000

---------------------

So, to 3 decimal places, the chance of getting a result that skewed is 0.000.

This is not the first time I've heard flaky numbers from PartyPoker. I would steer clear of this game.
 
Last edited:
KenSmith

KenSmith

Administrator
Staff member
#8
#8
Since the online calculator returned a value of zero, I decided to run this test in Excel instead. The result?
1.2094E-40, or
0.00000000000000000000000000000000000000012094
This is quite likely beyond any meaningful precision limits of Excel, so just call it ZERO.

A second independent set of data would be quite useful to see.
 
S

ScottH

Well-Known Member
#9
#9
I don't know whether or not PP blackjack is rigged, but back in the day when I was a gambler I had both really good, and really bad results. It wasn't just on the negative side...

However, my massive positive run was right at the beginning, and it was only downhill from there. They could rig it to do good for you to suck you in, and then "flip the switch" or something, I don't know.
 
S

ScottH

Well-Known Member
#12
#12
The only problem here is nobody comes on to post, "Hey, I had results 10 st. dev. above the mean, PartyPoker is NOT rigged!". We are only hearing about the extreme negative sides because that motivates people to come on here and question the results. There very well could be many people who have had rediculous wins, many std. deviations above the mean as well.

Although, 15 standard deviations below the mean is pretty rough... All I can say is, WHY WERE YOU EVEN PLAYING?!
 
K

Kasi

Well-Known Member
#13
#13
aka23 said:
Were you playing single-hand or multi-hand?
Click to expand...
I would think that would make a huge difference.


Clearly, playing one hand at a time against the dealer betting $1 losing $1000 over 3500 hands is impossible.

How many dealer upcards were there?
 
K

Kasi

Well-Known Member
#14
#14
ScottH said:
The only problem here is nobody comes on to post, "Hey, I had results 10 st. dev. above the mean, PartyPoker is NOT rigged!".
Click to expand...
Probably because that's never happened either.

Can u even express the odds as 1 in X of an event being 10 standard deviations?

I don't think I can. Way way over trillions to 1.
 
S

ScottH

Well-Known Member
#15
#15
Kasi said:
Probably because that's never happened either.
Click to expand...
Haha, maybe. Although like I said I did have a good run on PartyPoker in the beginning. I played the martingale starting from 5 dollars and I made a lot of money before the eventual collapse.
 
D

dacium

Well-Known Member
#16
#16
I need to clean something up, firstly it was not $1000 lost betting $1 per hand in 3500 hands. At times we played 2 hands at once, $2 on each and a rare playing of $4 per hand and playing upto 4 squares (two each).

This is why I am was going on the dealer up card rather than the expected value, because the bets varied (i flat betted $1 only to loose the first $100).

Also I will code a perl script to record the number of blackjacks for us and for the dealer. Trying to get double downs is more harder... though :-( but it seemed we lost HEAPS of them.
 
S

ScottH

Well-Known Member
#17
#17
dacium said:
I need to clean something up, firstly it was not $1000 lost betting $1 per hand in 3500 hands. At times we played 2 hands at once, $2 on each and a rare playing of $4 per hand and playing upto 4 squares (two each).
Click to expand...
It's pretty easy to get confused about that when you write this

dacium said:
My friend and I just had an insane loosing streak on party poker multi blackjack. we lost about $1000 in 3500 hands playing basic strategy flat betting $1.
Click to expand...
So... it looks like the 15 standard deviations below the mean is not true anymore. Just another bad beat story in my opinion...
 
Sonny

Sonny

Well-Known Member
#18
#18
ScottH said:
So... it looks like the 15 standard deviations below the mean is not true anymore. Just another bad beat story in my opinion...
Click to expand...
The 15 SD was in reference to the dealer’s upcards, not his overall results. I believe that’s why he chose to analyze the upcards instead. He knew that the bets were not constant so he found something that should have been. In this case his win/loss results are meaningless. The probability of that distribution of dealer upcards is 0.00%.

-Sonny-
 
S

ScottH

Well-Known Member
#19
#19
Sonny said:
The 15 SD was in reference to the dealer’s upcards, not his overall results. I believe that’s why he chose to analyze the upcards instead. He knew that the bets were not constant so he found something that should have been. In this case his win/loss results are meaningless. The probability of that distribution of dealer upcards is 0.00%.

-Sonny-
Click to expand...
Oh, thanks for clearing that up. The only thing is things with probabilities of 0.000001% still happen.

I heard a story about a lady who won a million dollars jackpot with one penny, twice. They said the odds of that were around 1 billion to 1. The odds of that would also be rounded to 0.00%, but it happened.

There is doubt that PartyPoker may be rigged, so nooone should play there. But why would you play there anyway? Unless of course they offer a bonus, but i don't think they match a 500 dollar bonus to make it cause you to lose 1000.
 
A

aka23

Well-Known Member
#20
#20
Sonny said:
The 15 SD was in reference to the dealer’s upcards, not his overall results. I believe that’s why he chose to analyze the upcards instead. He knew that the bets were not constant so he found something that should have been. In this case his win/loss results are meaningless. The probability of that distribution of dealer upcards is 0.00%.

-Sonny-
Click to expand...
I wrote the comment about the 15 SD. That was in reference to a loss of $1000 with 3500 $1 bets. The dealer upcards analysis was separate, and also indicated rare results.
 
Last edited:
You must log in or register to reply here.
Top