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Date: Wed, 28 Oct 1998 22:10:08 -0800 From: Alex Alten <Alten@home.com> Subject: Re: Shuffling

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From what I understand when one shuffles a deck of 52 cards 7 or more times

The concept of swapping to get a random string of bits is very interesting. the card order becomes unpredictable e.g. random.

Only if it is a 'fair' shuffle. There are poker players I've met who could put a given card anywhere in the deck after 4-5 shuffles.

The shuffle must be what is called a "near perfect" shuffle.

Perfect for who? Idealy the 'perfect' shuffle (if I understand your meaning of perfect) would be for each card in each deck-half to interleave 1-to-1. This does not produce random anything, it does make it very hard for people to count cards, which is why you shuffle - not to create a necessarily random ordering of the cards, just so mis-ordered nobody can remember what the sequence was and predict reliably what the sequence will be. This is incredibly important in games like poker or rummie where the cards pile up and players can see the sequence (and if they can remember it use it). This is also the reason that all games involving shuffled cards strictly call for a neutral party to shuffle and deal, falling back to the players only for 'friendly' games. Really smart 'amateur' players as you call them also make sure that he who deals is not he who anties first. I've never quite understood where this 'shuffle equal random' theory so many people have comes from (historicaly). But it is fun to play against them because they also (usualy) only shuffle the cards once to twice before a deal. Even un-even shuffles aren't prevention from short-sequence card counters. I impliment this when I play poker, it's helpfull to figure out how many cards to draw because it's possible to estimate the 'distance' between a short set of cards (eg a royal flush) after the shuffle.

In other words the cards can't strictly alternate from each hand (with a half deck each), but must be slightly random, in the sense that sometimes 2 or 3 cards may drop from a hand before a card drops from the other hand.

Unfortunately, professional croupie's don't practice for this. They practice for a perfect inter-leave.

An amateur shuffle, like the one I perform, where the cards clump as they drop, may require 100's of iterations before the order becomes totally unpredictable. BTW, if I remember correctly the number of people in the world who can execute a perfect shuffle at a professional rate (about 8 times a minute?) consistently is somewhat less than 30.

8 time a minute? That's a pretty slow shuffle. Where did you get this number from? A really quick proffessional shuffle doesn't take 3 seconds. ____________________________________________________________________ To know what is right and not to do it is the worst cowardice. Confucius The Armadillo Group ,::////;::-. James Choate Austin, Tx /:'///// ``::>/|/ ravage@ssz.com www.ssz.com .', |||| `/( e\ 512-451-7087 -====~~mm-'`-```-mm --'- --------------------------------------------------------------------