

How many times should you shuffle a deck of cards? [pdf] - TriinT
http://www.dartmouth.edu/~chance/teaching_aids/Mann.pdf

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jazzychad
Related: <http://news.ycombinator.com/item?id=966243> (uses some of the same
probabilistic models and rising sequences)

I also wrote a simple javascript card-shuffling library based on these models
after reading the davidson.edu article: <http://jazzychad.com/js/deck.php>

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xenophanes
so, how many times?

i read parts of the pdf but didn't find the answer. i did see it say 7 isn't
enough.

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trebor
Basically, "the more the better". In lieu of a summary, let me try to see if I
understand it.

The deck is more random: the more times you shuffle, the more cuts you make,
and the more you randomize the size of your cuts. To draw my own conclusion,
the more chaos you throw into your method (which may even include lesser
amounts of shuffling) the better the randomness of the deck should be.

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anamax
> Basically, "the more the better".

Actually, no. Too much shuffling actually makes some sequences less likely.

See [http://www-
stat.stanford.edu/~susan/courses/b494/index/node1...](http://www-
stat.stanford.edu/~susan/courses/b494/index/node109.html)

For some simpler math for a related question, see
[http://20bits.com/articles/interview-questions-shuffling-
an-...](http://20bits.com/articles/interview-questions-shuffling-an-array/)

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Me3748594
6

