online poker's "shuffling"

The_Gamblar

is it just me or does there seem to be more suited flops than ever .. considering that it is only a 5% chance of a 3 suited flop .. i see it more and more.. at sites like pokerstar there isn't as much as sites like pokerroom but i see it 1-2 outa every 10 times.. is the distribution of the 52 cards actually random?.. can there be a possbility of a glitch?.. we all know that a 52 card can but shuffled as "52!".. but is it the same as a human shuffling the cards.. in your home games how long do u shuffle them do u do a shuffle a bridge and a cut or do u just mix them together.. cuz i sure as hell don't get as many 3 suited flops as online poker does..

ScottyZ

It's just you.

ScottyZ

TreC

It's completely random. I designed a computer blackjack game in college and have a very good idea how they "shuffle" the cards.

Unknown

While we're on the topic, I have what I'm sure is a *very* stupid question. But, I'm going to ask it anyways.

Are the cards that come off on the board predetermined online? By this, I mean: in a B&M game, the turn card is the card in the deck after the burn card. Online, are there 52 randomly shuffled cards that stay in that order for the duration of the hand, or do they pick one card at random to be, say, the turn card, of the cards that are left?

Did that make sense?

I know it really doesn't make any difference whatsoever. A random card is a random card. I was just curious as to whether or not this random card comes from a specific spot in a shuffled virtual 'deck'.

Regards,
all_aces

ps: if this question is too stupid to answer, or to speculate about, I won't be offended if nobody replies...

RoyalFlush

All_aces, I understand what you are saying, but I am sure no one on here will know. Only those who operate the program running the dealer. Otherwise it's impossible to find out.

It's one of those questions like does the refridgerator light turn off when you close it?

Unknown

It's one of those questions like does the refridgerator light turn off when you close it?

Lol, fair enough. Can't blame a guy for asking tho!

Regards,
all_aces

professor

I think the way it goes is this....

Each table online is running its own little bit of code on the server. When it needs a new shuffled deck of cards it "pings" another part of the server and is sent a new shuffled deck. That's why you see
"Deal Number 6523567172" or so forth in one corner of the screen. Then the local software for that table takes over and distributes the cards as appropriate (holdem, 7-stud, etc). So (I think) the answer is that a shuffled 52 card deck is sent to each online table as it is needed.

ScottyZ

It's one of those questions like does the refridgerator light turn off when you close it?

Nope. I just checked like five times.

I did a Google search for "PokerStars shuffling algorithm" and found this:

To perform an actual shuffle, we use another simple and reliable algorithm:
-first we draw a random card from the original deck (1 of 52) and place it in a new deck - now original deck contains 51 cards and the new deck contains 1 card
-then we draw another random card from the original deck (1 of 51) and place it on top of the new deck - now original deck contains 50 cards and the new deck contains 2 cards
-we repeat the process until all cards have moved from the original deck to the new deck

That sounds to me like they have the whole shuffled deck ready to go (i.e. the "new deck") before the hand starts.

I know it really doesn't make any difference whatsoever. A random card is a random card. I was just curious as to whether or not this random card comes from a specific spot in a shuffled virtual 'deck'.

In some cases it does matter. For example, suppose there are two spades on board and you have top two pair. Now a third spade falls on the river.

If the shuffling took place before the hand, you say

"I *knew* a spade was coming."

If the cards are selected individually at random from an unshuffled deck as they are needed, you say

"I *knew* the hardware random number generator, thermal noise entropy source, and external user-based entropy source were going to be such that a spade would be selected."



For enough discussion of how to shuffle cards for online poker using a computer to make the average person wish he had never asked about how to shuffle cards for online poker using a computer, see:

http://itmanagement.earthweb.com/entdev/article.php/616221

So (I think) the answer is that a shuffled 52 card deck is sent to each online table as it is needed.

Wouldn't it be cooler if PokerStars had a team of monkeys who shuffled actual decks of cards and passed them to the PokerStars computer-type guys using one of those old school "stuff your message in a cylinder and put it into a complex network of air pressure driven tubes" thigamajig?

I'll bet that would also avoid "Bad Distribution Of Shuffles".

Plus, players could better focus their bad beat anger.

"Damn monkeys."

ScottyZ

DJP

Awww, I was gonna use the word algorithm. lol

Aren't those players who have nowhere to focus their bad beat anger easier prey?

kwplayer

I have looked into this a little bit and I remember seeing a place that did their shuffling by assigning each card in the deck a very large random number and then sorting those random numbers. I can't recall but I think the number was somewhere in the order of 2^32.

Ultimate bet (from what I read) actually has some hardware where they get their random number from the frequency of some sort of volitile material. Can't remember exactly, but this seemed quite excessive.

Most of these cardrooms have their shuffling algorithm tested by a third party to ensure "randomness". I think they take a big sample of decks and then ensure they are coming up in the proper frequency or something ...

.kw

Having said all this, I can't see how it is any less random then some clown dealing you some cards in a casino. Half of them can't shuffle right, so I suspect there is much more chance of "bunching" to happen in live poker that could not happen in online poker. Hey Jacks have been flopping all night! LOL

ScottyZ

Having said all this, I can't see how it is any less random then some clown dealing you some cards in a casino.

Not to mention home game shuffling. I once witnessed someone essentially repeatedly *cutting* the deck and trying to pass this off as shuffling.

Ultimate bet (from what I read) actually has some hardware where they get their random number from the frequency of some sort of volitile material. Can't remember exactly, but this seemed quite excessive.

This seemed excessive to me at first also, but the more I thought about this, I came to realize you really do have to be careful seeding your random number generator in such a way that an attacker couldn't predict the next hand, even if the attacker knew the entire method used to generate the random numbers, and had the identical RNG hardware and software.

The attacker would still be foiled if they didn't know the precise temerature of the air 25cm above toaster #3B in the PokerStars snack room.

ScottyZ

ScottyZ

at sites like pokerstar there isn't as much as sites like pokerroom but i see it [a three flush flop] 1-2 outa every 10 times..

We need more information here.

1. How many total flops have you observed?

2. How many hands was a flop not seen? If there is a significant number of unseen flops, this creates a small bias in whether or not the *seen* flops are 3 suited. We can probably assume this particular bias is negligible, especially is a loose pre-flop game.

3. Exactly how many flops were three suited? Your hypothesis of 1 or 2 occurances every 10 is too inexact. For example, in a sample of 100 hands the probability of seeing 10 or more three suited flops (at least 1 out of 10) is around 3%. That's far from astronomical.

>> binocdf(90,100,0.95)

ans =

0.0282


The probability of seing at least 20 three suited hands (at least 2 out of 10) is about 10^(-7), or 10 million to 1 odds against. Pretty unlikely.

>> binocdf(80,100,0.95)

ans =

1.0523e-07

ScottyZ