Is there any truth to the premise that the cards can get nonrandom due to the pickup/game play? ie two tens stand pat, so they stay together, and a dealer pulling a bunch of small cards keeps those cards together in the pickup.
Does the shuffle destroy these clumps? I just seem to see so many games where 5 face cards come out in a row, then a bunch of 3s and 4s to give players a bunch of stiff hands. Perhaps this is just bad luck on my part?
In Stanford Wong's book there's a big section with the self-explanatory title "Search for Streakiness". The key points:
"The re-arrangement of cards for the situation tested, namely one player, lay and pay, and six decks, results in the player being 0.70% to 0.75% better off than if the cards were shuffled."
...
"In general, the difference between well-shuffled cards and unshuffled cards is that if the cards are not shuffled, high cards tend to follow high cards and small cards tend to follow small cards."
...
"Streakiness does not exist at the two extremes, when cards are well-shuffled and when they are not shuffled [at all]. Since streakiness does not exist at both extremes, it does not exist betwene the extremes. That is, streakiness does not exist, regardless of the amount of shuffling."
Yea, the ebb and flow of cards that do not stand up to stastics is a big part of my in-and-out game, even at 2 and sigle deck.
a dealer intentionally hi-lowing a deck. It is an intentional cheating move based on the dealer picking up discards in a manner different than house procedures call for. You won't find it in a big casino and, due to it's obvious nature before your eyes, you are unlikely to find it anywhere at all anymore.
First, scenarios such as you have described are going to occur even in a truly "random" shuffle. Indeed, if they did not, then the shuffle would not be truly "random."
In days past, especially with what was called the "stutter shuffle," there was a considerable amount of what you descibe, which is termed "like-card bunching" or "like-card clumping."
In Atlantic City, back in the mid- and late '70s, I personally observed *many* instances of a fresh round being dealt to a full table of 7 players where no card was greater than a 6; and many others where every card showing was an Ace or ten. The probabilities of such events occuring are so astronomically low; you should not see such an event more than once or twice in 1,000 lifetimes; yet I would see it 3 or 4 times each trip.
When using a computer to analyze the result of such shuffles, I found that pairs (2 adjacent cards in the newly shuffled shoe of identical value -- the ultimatate "like-card bunch") occured approximately 3% more often than the math said should occur.
Fortunately, the stutter shuffle is pretty much a thing of the past, and has been almost universally replaced by the automatic shuffling machines. The last place I've a stutter shuffle in use was the Imperial Palace in Biloxi. But that was over a year ago (May, '01); so (hopefully) may have changed.
My analysis of the "ShuffleMaster" machine shuffle shows no higher incidence of pairs (contiguous identical value cards) in the shoe than there should be.
So, the real answer to your question is: "Yes, like-card bunching used to occur in certain cases and places; but, No, you don't worry too much about it any more."
The existence or non-existence of like-card bunching has been a big controversy for a long time. Some have tried to use the results of non-shuffled cards to discredit it.
But non-shuffling does not have anywhere near the same effect of under-shuffling.
In the stutter shuffle, the top and bottom (roughly) half decks in the shoe (before the cut) are the outcome of two riffles, and the middle cards (e.g., the middle 5 decks of a 6-deck shoe) were the outcome of three riffles. After the cut, the (roughly) one deck worth of cards which received only two riffles always became contiguous. Indeed, at the time, the rule in Atlantic City was that you had to cut at least 1/2 deck from either "end" of the shoe, which *guaranteed* those two half-decks would become contiguous.
So, what occured in the mechanics of the stutter shuffle was that the majority of the small bunches created during the normal course of play were broken up, but *some* were shuffled into each other thus creating a larger "like-card bunch." On the next riffle, the same thing occured: the majority of the larger bunches were destroyed, but *some* were increased still larger. The same thing would occur a 3rd time on that portion of the shoe which got a 3rd riffle.
Thus, the under-shuffling, and the *type* of under-shuffling in the stutter shuffle, had a *much* greater effect on the production of *a few* LARGE like-card bunches in the shoe; while non-shuffling only leaves the many small like-card bunches created during the normal course of play.
Thus, IMHO, it is simply *not* valid to compare the results of non-shuffling to the results produced by the old stutter shuffle.
simply by playing an uneven number of hands!
If the dealer doesn't deal seconds, the player(s) would win a horrendous percentage of hands.
Francis Salmon
... from the King os Streakiness. (Was that you at Wimbledon? :-})
Agree with most all you say, but I would stress the words: "the starting point for 'streak players'..." And it's a long looooong road from that start to any profits. And nobody is going to hold your hand on that bus ride!
Regards,
ETF
