Why Does Reshuffling a Deck Reset Card Counting Probabilities?

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    Mechanics Probability
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Discussion Overview

The discussion revolves around the implications of reshuffling a deck of cards in blackjack on the probabilities associated with card counting. Participants explore the relationship between the reshuffling process and the perceived probabilities of drawing certain cards, questioning the underlying mechanics of this phenomenon.

Discussion Character

  • Exploratory, Debate/contested, Conceptual clarification

Main Points Raised

  • One participant notes that after calculating a probability of drawing a 10 or higher, reshuffling seems to nullify that probability, prompting a question about the underlying reasons for this change.
  • Another participant asserts that reshuffling does not relate to quantum mechanics, suggesting that the probability remains unchanged regardless of the reshuffle if the count of known cards is considered.
  • A further inquiry is made about whether the reshuffle includes all previously dealt cards, implying that if these cards are included, the odds would indeed change.
  • A participant acknowledges a flaw in their analogy regarding the reshuffling and expresses a need to rethink their approach to the topic.

Areas of Agreement / Disagreement

Participants express differing views on the impact of reshuffling on card probabilities, with some asserting that the reshuffle does not affect the count while others suggest it does. The discussion remains unresolved regarding the exact nature of the probabilities post-reshuffle.

Contextual Notes

There are assumptions about the handling of previously dealt cards during reshuffling that are not fully explored, leading to potential ambiguity in the discussion of probabilities.

billy_boy_999
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if I'm counting cards in blackjack and at some point work out that the probability of the next card being dealt being a 10 or higher is 2/1, and the dealer suddenly reshuffles the deck, that probability evaporates (ask any card counter)...but why? what is going on here? reshuffling the deck doesn't alter which cards have been dealt so it doesn't alter the count that led to my 2/1 probability, so what then does it alter? is there some explanation that comes from quantum mechanics? does it have to do with wave functions?
 
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Nothing to do with quantum mechanics. If 2 cards out of three are higher than ten, no matter reshuffling.
 
When the dealer reshuffles, does he include all the known cards previously dealt and no longer in play? If so, the odds do change.
 
ohohohoho! you're right! this is a corrupt analogy, thank you for the replies anyway...i'll have to try and think of another way to address this topic...
 

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