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Groups > comp.lang.python > #92708
| Newsgroups | comp.lang.python |
|---|---|
| Date | 2015-06-16 16:26 -0700 |
| References | (7 earlier) <5515034.V7dcXEWAvK@PointedEars.de> <88ba163e-74f4-40fa-ab3e-1feeb051b961@googlegroups.com> <17701105.fuEQZlnPee@PointedEars.de> <ff4a8ffd-50fe-4705-b33a-fcf63bcccc11@googlegroups.com> <2089101.KkvqnN9Xah@PointedEars.de> |
| Message-ID | <dfc293e6-01b8-4179-92c3-2d7c2ffcbbe8@googlegroups.com> (permalink) |
| Subject | Re: Testing random |
| From | Ned Batchelder <ned@nedbatchelder.com> |
On Tuesday, June 16, 2015 at 6:01:06 PM UTC-4, Thomas 'PointedEars' Lahn wrote:
> Ned Batchelder wrote:
>
> > [...]
> > This is done empirically, by producing `nseq` sequences of
> > `nrolls` rolls of the die. Each sequence is examined to
> > see if it has a zero. The total number of no-zero
> > sequences divided `nseq` is the probability.
>
> No, it is not. It is the relative frequency for *this* number of trials and
> *this* run of the experiment.
>
> > """
> > no_zeros = 0
> > for _ in xrange(nseq):
> > seq = die_rolls(nrolls)
> > if not any_zeros(seq):
> > no_zeros += 1
> > return float(no_zeros)/nseq
> >
> > for n in range(10, 101, 10):
> > # Calculate the probability of getting no zeros by trying
> > # it a million times.
> > prob = probability_of_no_zero(n, 1000000)
> > print "n = {:3d}, P(no zero) = {:.8f}".format(n, prob)
> >
> >
> >
> > Running this gives:
> >
> > $ pypy testrandom.py
> > n = 10, P(no zero) = 0.34867300
> > n = 20, P(no zero) = 0.12121900
> > n = 30, P(no zero) = 0.04267000
> > n = 40, P(no zero) = 0.01476600
> > n = 50, P(no zero) = 0.00519900
> > n = 60, P(no zero) = 0.00174100
> > n = 70, P(no zero) = 0.00061600
> > n = 80, P(no zero) = 0.00020600
> > n = 90, P(no zero) = 0.00006300
> > n = 100, P(no zero) = 0.00002400
> >
> >
> > As n increases, the probability of having no zeros goes down.
>
> Your programmatic "proof", as all the other intuitive-empirical "proofs",
> and all the other counter-arguments posted before in this thread, is flawed.
> As others have pointed out at the beginning of this thread, you *cannot*
> measure or calculate probability or determine randomness programmatically
> (at least not with this program).
You *can* estimate probability with a program, which is what is happening
here.
> I repeat: Probability is what relative
> frequency (which you can measure) *approaches* for *large* numbers. 100 is
> anything but large, to begin with.
The number of trials in this program is not 100, it is 1 million. You seem
uninterested in trying to understand.
> What is "large" depends on the
> experiment, not on the experimentator. And with independent events, the
> probability for getting zero does not increase because you have been getting
> non-zeros before. It simply does not work this way.
Again, if you look at the code, you'll see that we are not talking about
the probability of getting a zero on the next roll. We are talking about the
probability of getting no zeros in an N-roll sequence. I have no idea how you
have misunderstood this for so long.
I'll stop trying to explain it.
--Ned.
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Testing random Cecil Westerhof <Cecil@decebal.nl> - 2015-06-07 08:27 +0200
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 12:40 +0200
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-07 21:51 +1000
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 17:51 +0200
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 02:25 +1000
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 18:36 +0200
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 02:44 +1000
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 20:23 +0200
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 04:52 +1000
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 21:41 +0200
Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-07 22:08 +0300
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 21:29 +0200
Re: Testing random random832@fastmail.us - 2015-06-07 15:44 -0400
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 22:09 +0200
Re: Testing random random832@fastmail.us - 2015-06-07 16:41 -0400
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 22:59 +0200
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 11:26 +1000
Re: Testing random random832@fastmail.us - 2015-06-07 21:34 -0400
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 11:42 +1000
Re: Testing random MRAB <python@mrabarnett.plus.com> - 2015-06-08 02:49 +0100
Re: Testing random random832@fastmail.us - 2015-06-07 21:57 -0400
Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-08 10:40 +0300
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-10 19:03 +0200
Re: Testing random sohcahtoa82@gmail.com - 2015-06-10 10:52 -0700
Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-10 23:00 +0300
Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-10 12:02 -0600
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-12 23:32 +0200
Re: Testing random alister <alister.nospam.ware@ntlworld.com> - 2015-06-12 21:46 +0000
Re: Testing random random832@fastmail.us - 2015-06-12 17:52 -0400
Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-12 16:00 -0600
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-13 00:09 +0200
Re: Testing random sohcahtoa82@gmail.com - 2015-06-12 15:55 -0700
Re: Testing random random832@fastmail.us - 2015-06-12 18:57 -0400
Re: Testing random Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-06-13 08:53 +0100
Re: Testing random random832@fastmail.us - 2015-06-10 14:26 -0400
Re: Testing random Ned Batchelder <ned@nedbatchelder.com> - 2015-06-07 14:21 -0700
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-16 21:18 +0200
Re: Testing random random832@fastmail.us - 2015-06-16 16:23 -0400
Re: Testing random Ned Batchelder <ned@nedbatchelder.com> - 2015-06-16 13:48 -0700
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-16 23:57 +0200
Re: Testing random sohcahtoa82@gmail.com - 2015-06-16 15:30 -0700
Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-16 16:58 -0600
Re: Testing random Laura Creighton <lac@openend.se> - 2015-06-17 11:28 +0200
Re: Testing random Ned Batchelder <ned@nedbatchelder.com> - 2015-06-16 16:26 -0700
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-17 01:45 +0200
Re: Testing random sohcahtoa82@gmail.com - 2015-06-16 17:36 -0700
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-17 11:01 +1000
Re: Testing random Ethan Furman <ethan@stoneleaf.us> - 2015-06-16 18:32 -0700
Re: Testing random Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-06-17 09:41 +0100
Re: Testing random Grant Edwards <invalid@invalid.invalid> - 2015-06-17 14:04 +0000
Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-17 09:01 -0600
Re: Testing random MRAB <python@mrabarnett.plus.com> - 2015-06-17 01:42 +0100
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-17 08:53 +0200
Re: Testing random Christian Gollwitzer <auriocus@gmx.de> - 2015-06-17 09:22 +0200
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-17 17:28 +1000
Re: Testing random Tim Golden <mail@timgolden.me.uk> - 2015-06-17 08:30 +0100
Re: Testing random Cecil Westerhof <Cecil@decebal.nl> - 2015-06-17 11:57 +0200
Re: Testing random Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-06-17 01:36 +0000
Re: Testing random Laura Creighton <lac@openend.se> - 2015-06-17 12:33 +0200
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-17 22:47 +1000
Re: Testing random Laura Creighton <lac@openend.se> - 2015-06-17 15:50 +0200
Re: Testing random Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-06-17 01:35 +0000
Re: Testing random Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2015-06-17 07:41 +0300
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 11:11 +1000
Re: Testing random Ian Kelly <ian.g.kelly@gmail.com> - 2015-06-07 11:07 -0600
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 03:20 +1000
Re: Testing random "C.D. Reimer" <chris@cdreimer.com> - 2015-06-07 10:36 -0700
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 04:28 +1000
Re: Testing random Chris Angelico <rosuav@gmail.com> - 2015-06-08 04:40 +1000
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 04:24 +1000
Re: Testing random Jonas Wielicki <jonas@wielicki.name> - 2015-06-07 12:41 +0200
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-07 22:52 +1000
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-07 23:06 +1000
Re: Testing random Peter Otten <__peter__@web.de> - 2015-06-07 15:35 +0200
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 18:36 +0200
Re: Testing random Peter Otten <__peter__@web.de> - 2015-06-07 18:48 +0200
Re: Testing random Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-07 22:15 +0200
Re: Testing random Steven D'Aprano <steve@pearwood.info> - 2015-06-08 11:35 +1000
Re: Testing random Christian Gollwitzer <auriocus@gmx.de> - 2015-06-07 14:53 +0200
Re: Testing random Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2015-06-07 11:04 -0400
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