Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.c > #14600

Re: Toughest Probability Question

From "BartC" <bc@freeuk.com>
Newsgroups comp.lang.c
Subject Re: Toughest Probability Question
Date 2011-12-14 12:12 +0000
Organization A noiseless patient Spider
Message-ID <jca3se$pln$1@dont-email.me> (permalink)
References (4 earlier) <slrnjee4qh.2irh.usenet-nospam@guild.seebs.net> <jc7kqo$egv$1@dont-email.me> <slrnjef9k1.30f0.usenet-nospam@guild.seebs.net> <jc8oom$ku5$2@dont-email.me> <slrnjefr5m.7q7.usenet-nospam@guild.seebs.net>

Show all headers | View raw


"Seebs" <usenet-nospam@seebs.net> wrote in message 
news:slrnjefr5m.7q7.usenet-nospam@guild.seebs.net...
> On 2011-12-13, BartC <bc@freeuk.com> wrote:
>> So what *is* the probability that out of a group of 23 people, at least 
>> two
>> will share a birthday?

> Consider it a philosophical point -- but perhaps a significant one. 
> People
> who have studied probability but not thought carefully about the 
> assumptions
> make a LOT of mistakes in evaluating the probabilities of events in the
> real world.

Probability is a useful mathematical tool. There will be discrepancies when 
applied to real-life situations, but that in itself can be useful, when you 
investigate why.

In the case of real-life groupings of two dozen or more people that you 
might typically find (even if you have no idea why any particular gathering 
has occurred) I don't think the theoretical probabilities are going to that 
different from actual results.

So if you're at a party with some 60 people, I believe even you would take 
on a bet against someone who didn't think anyone would share a birthday. (I 
believe the theoretical probability is about 99%; someone who hasn't thought 
it about it too carefully, and might be also be drunk, might think it was 
16%).

>
> To bring this vaguely on topic:
>
> You have a pointer which contains stack garbage.  Your process has a
> 4MB memory footprint in a 4GB address space.  What are the chances that 
> the
> pointer will point into your memory footprint?
>
> Hint:  They're almost certainly not 1/1024.

I've no idea. The answer could be anything. However I wouldn't try 
dereferencing such a pointer, even if the probability was 100%.

-- 
Bartc 

Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread


Thread

Re: Toughest Probability Question pete <pfiland@mindspring.com> - 2011-12-12 19:29 -0500
  Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-13 04:46 +0000
    Re: Toughest Probability Question Geoff <geoff@invalid.invalid> - 2011-12-12 22:19 -0800
      Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-13 09:19 +0000
        Re: Toughest Probability Question "BartC" <bc@freeuk.com> - 2011-12-13 13:43 +0000
          Re: Toughest Probability Question Keith Thompson <kst-u@mib.org> - 2011-12-13 10:27 -0800
            Re: Toughest Probability Question "BartC" <bc@freeuk.com> - 2011-12-13 19:52 +0000
              Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-13 20:06 +0000
              Re: Toughest Probability Question Keith Thompson <kst-u@mib.org> - 2011-12-13 12:14 -0800
                Re: Toughest Probability Question "BartC" <bc@freeuk.com> - 2011-12-13 23:34 +0000
                Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-14 00:24 +0000
          Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-13 19:27 +0000
            Re: Toughest Probability Question "BartC" <bc@freeuk.com> - 2011-12-13 23:56 +0000
              Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-14 00:24 +0000
                Re: Toughest Probability Question "BartC" <bc@freeuk.com> - 2011-12-14 12:12 +0000
                Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-14 17:47 +0000
                Re: Toughest Probability Question gordonb.qunma@burditt.org (Gordon Burditt) - 2011-12-15 08:22 -0600
                Re: Toughest Probability Question Robert Wessel <robertwessel2@yahoo.com> - 2011-12-15 14:41 -0600
                Re: Toughest Probability Question superpollo <superpollo@tznvy.pbz> - 2011-12-15 19:14 +0100
                Re: Toughest Probability Question Keith Thompson <kst-u@mib.org> - 2011-12-14 13:12 -0800
                Re: Toughest Probability Question Willem <willem@toad.stack.nl> - 2011-12-14 21:53 +0000
                Re: Toughest Probability Question "BartC" <bc@freeuk.com> - 2011-12-14 22:35 +0000
                Re: Toughest Probability Question Willem <willem@toad.stack.nl> - 2011-12-15 09:07 +0000
                Re: Toughest Probability Question Geoff <geoff@invalid.invalid> - 2011-12-15 02:07 -0800
                Re: Toughest Probability Question Keith Thompson <kst-u@mib.org> - 2011-12-15 12:13 -0800
                Re: Toughest Probability Question Geoff <geoff@invalid.invalid> - 2011-12-15 13:03 -0800
                Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-15 21:36 +0000
              Re: Toughest Probability Question Geoff <geoff@invalid.invalid> - 2011-12-13 16:35 -0800
                Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-14 01:20 +0000
              Re: Toughest Probability Question Keith Thompson <kst-u@mib.org> - 2011-12-13 16:44 -0800
                Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-14 01:20 +0000
                Re: Toughest Probability Question James Dow Allen <jdallen2000@yahoo.com> - 2011-12-15 02:33 -0800
                Re: Toughest Probability Question gwowen <gwowen@gmail.com> - 2011-12-15 05:38 -0800
                Re: Toughest Probability Question Thad Smith <ThadSmith@acm.org> - 2011-12-18 23:34 -0700
                Re: Toughest Probability Question Bill Reid <hormelfree@gmail.com> - 2011-12-14 07:07 -0800
    Re: Toughest Probability Question Kaz Kylheku <kaz@kylheku.com> - 2011-12-13 06:55 +0000
      Re: Toughest Probability Question Seebs <usenet-nospam@seebs.net> - 2011-12-13 09:19 +0000
    Re: Toughest Probability Question pete <pfiland@mindspring.com> - 2011-12-13 12:15 -0500
      Re: Toughest Probability Question pete <pfiland@mindspring.com> - 2011-12-13 13:20 -0500
        Re: Toughest Probability Question Peter Nilsson <airia@acay.com.au> - 2011-12-13 18:15 -0800
          Re: Toughest Probability Question pete <pfiland@mindspring.com> - 2011-12-13 21:52 -0500

csiph-web