Alexxx: randomness of cards

[Alexxx]

Card counting is based on the premise that cards are random.
According to "TRAILING THE DOVETAIL SHUFFLE TO ITS LAIR",
12.43 times riffle shuffle is needed to make 312 cards random enough.
So, card counting is not effective on 1st and 2nd or 3rd shoes after "show cards"?

TRAILING THE DOVETAIL SHUFFLE TO ITS LAIR

[GMan]

> Card counting is based on the premise that cards are
> random.

FALSE ! Card counting is based on the nature of the remaining cards to be dealt. I DON'T EVEN CARE IF x% OF THE TIME THEY ARE BEHIND THE CUT CARD because the other y% of the time they will be dealt to me. No BS on this site please, the net is big enough to try your tricks somewhere else.

[David Spence]

I'm not so sure about your interpretation of it, but the paper itself is fascinating. It even includes an impressive magic trick as a bonus :-)

[Alexxx]

> Card counting is based on the nature of the
> remaining cards to be dealt.
I agree.
AND, I think, card counting is based on the premise that cards are random.
There may be difference between TC2 of well shuffled deck and TC2 of not well shuffled deck.

[Norm Wattenberger]

How to you riffle cards 12.43 times?

> Card counting is based on the premise that cards are
> random.
> According to "TRAILING THE DOVETAIL SHUFFLE TO
> ITS LAIR",
> 12.43 times riffle shuffle is needed to make 312 cards
> random enough.
> So, card counting is not effective on 1st and 2nd or
> 3rd shoes after "show cards"?

[Norm Wattenberger]

The study does not apply to BJ. A normal deck has 52 different cards. In BJ there are only ten different cards. The difference is vast.

> I agree.
> AND, I think, card counting is based on the premise
> that cards are random.
> There may be difference between TC2 of well shuffled
> deck and TC2 of not well shuffled deck.

[THE PLAYER]

> The study does not apply to BJ. A normal deck has 52
> different cards. In BJ there are only ten different
> cards. The difference is vast.

Norm,

there are only 2 different cards in BJ. Did you forget?
small cards(2-6) and high cards10-ace).:-)

pl

[Don Schlesinger]

Just for the record, Perci Diaconis was a childhood friend of mine. We went to elementary school together, and, for many, many years, we lost track of each other.

When I read his article, which was the cover story of the Sunday NY Times Magazine, you can imagine how excited I was to learn who he had become.

I called him at Harvard, and we chatted for a long time.

Bottom line: Single decks do NOT have to be "perfectly" randomized to make playing blackjack a fair game. They just have to be "random enough," and you don't need 12+ shuffles to accomplish that! :-)

Don

[21forme]

> How to you riffle cards 12.43 times?

It can be done by the average family with 2.2 children.

[Alexxx]

Don & Norm, thank you very much for your valuable advice.
I always do bet up and down from second shoe after "show cards", because I think first shoe may not be random enough.
I'm just wondering, how many shuffles are "random enough".

[Mike H]

Does the casino "wash" the cards when they take them out of the pack? By washing I mean spread them on the table face down and mix them around with both hands. If so I would say they are "random enough". If you're not convinced the cards are adequately shuffled for the first shoe then don't invest any money in it, not even flat betting.