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Re: Cutting a deck of cards

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>> and in fact will probably make it worse depending on how you choose
>> the cutpoint.
 
> I'm pretty sure it won't. Otherwise you'd be lowering entropy by doing
> a random thing to a random thing.

Doing a random thing to a random thing usually *does* lower entropy when
the "random" things are actually deterministic algorithms that may have unexpected correlations. That's why you don't write your own PRNG unless
you have a very good understanding of the math.

If you are shuffling the deck with, say, numbers from random.org (which uses atmospheric noise), then cutting the deck afterward will have precisely 0 effect, since the (51 * 52!) possible outcomes include 51 copies of each of the 52! orderings, and so the odds of each end up the same. But if you're choosing the cutpoint by getting a value from the same PRNG you used to shuffle, there might very well be a correlation that makes some arrangements more likely
than others.

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Cutting a deck of cards RVic <rvince99@gmail.com> - 2013-05-26 10:52 -0700
  Re: Cutting a deck of cards MRAB <python@mrabarnett.plus.com> - 2013-05-26 19:04 +0100
  Re: Cutting a deck of cards Kamlesh Mutha <mkamlesh@gmail.com> - 2013-05-26 23:35 +0530
  RE: Cutting a deck of cards Carlos Nepomuceno <carlosnepomuceno@outlook.com> - 2013-05-26 21:16 +0300
    Re: Cutting a deck of cards Marc Christiansen <usenetmail@solar-empire.de> - 2013-05-26 21:36 +0200
      RE: Cutting a deck of cards Carlos Nepomuceno <carlosnepomuceno@outlook.com> - 2013-05-26 22:54 +0300
        Re: Cutting a deck of cards Marc Christiansen <usenetmail@solar-empire.de> - 2013-05-26 22:13 +0200
      Re: Cutting a deck of cards Terry Jan Reedy <tjreedy@udel.edu> - 2013-05-26 17:03 -0400
  Re: Cutting a deck of cards RVic <rvince99@gmail.com> - 2013-05-26 11:17 -0700
  Re: Cutting a deck of cards Roy Smith <roy@panix.com> - 2013-05-26 14:21 -0400
  Re: Cutting a deck of cards Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-05-26 23:17 +0100
  RE: Cutting a deck of cards Carlos Nepomuceno <carlosnepomuceno@outlook.com> - 2013-05-27 01:30 +0300
  Re: Cutting a deck of cards Chris Angelico <rosuav@gmail.com> - 2013-05-27 08:42 +1000
  RE: Cutting a deck of cards Carlos Nepomuceno <carlosnepomuceno@outlook.com> - 2013-05-27 01:51 +0300
  Re: Cutting a deck of cards Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-05-26 23:56 +0100
  Re: Cutting a deck of cards Lee Crocker <leedanielcrocker@gmail.com> - 2013-05-31 04:56 -0700
    Re: Cutting a deck of cards Modulok <modulok@gmail.com> - 2013-05-31 12:54 -0600
    Re: Cutting a deck of cards Joshua Landau <joshua.landau.ws@gmail.com> - 2013-06-01 18:16 +0100
      Re: Cutting a deck of cards Lee Crocker <leedanielcrocker@gmail.com> - 2013-06-01 22:57 -0700
  Re: Cutting a deck of cards Giorgos Tzampanakis <giorgos.tzampanakis@gmail.com> - 2013-06-01 14:58 +0000

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