From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.emacs.gnus.general/35077 Path: main.gmane.org!not-for-mail From: Christoph Conrad Newsgroups: gmane.emacs.gnus.general Subject: Re: `user-mail-address' for message-ids Date: 28 Feb 2001 07:31:01 +0100 Organization: Gnus Information Center Sender: owner-ding@hpc.uh.edu Message-ID: References: <20010223133030.B14991@mastaler.com> Reply-To: Christoph Conrad NNTP-Posting-Host: coloc-standby.netfonds.no Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: main.gmane.org 1035170878 1059 80.91.224.250 (21 Oct 2002 03:27:58 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Mon, 21 Oct 2002 03:27:58 +0000 (UTC) Return-Path: Original-Received: from lisa.math.uh.edu (lisa.math.uh.edu [129.7.128.49]) by mailhost.sclp.com (Postfix) with ESMTP id 944BED049D for ; Wed, 28 Feb 2001 01:33:11 -0500 (EST) Original-Received: from sina.hpc.uh.edu (lists@Sina.HPC.UH.EDU [129.7.3.5]) by lisa.math.uh.edu (8.9.1/8.9.1) with ESMTP id AAB28206; Wed, 28 Feb 2001 00:32:24 -0600 (CST) Original-Received: by sina.hpc.uh.edu (TLB v0.09a (1.20 tibbs 1996/10/09 22:03:07)); Wed, 28 Feb 2001 00:31:29 -0600 (CST) Original-Received: from mailhost.sclp.com (postfix@66-209.196.61.interliant.com [209.196.61.66] (may be forged)) by sina.hpc.uh.edu (8.9.3/8.9.3) with ESMTP id AAA19694 for ; Wed, 28 Feb 2001 00:31:19 -0600 (CST) Original-Received: from quimby.gnus.org (quimby.gnus.org [195.204.10.139]) by mailhost.sclp.com (Postfix) with ESMTP id C63E9D049D for ; Wed, 28 Feb 2001 01:31:48 -0500 (EST) Original-Received: (from news@localhost) by quimby.gnus.org (8.9.3/8.9.3) id HAA16886 for ding@gnus.org; Wed, 28 Feb 2001 07:31:44 +0100 (CET) Original-To: ding@gnus.org Original-Path: not-for-mail Original-Newsgroups: gnus.ding Original-NNTP-Posting-Host: ae720.pppool.de Original-X-Trace: quimby.gnus.org 983341903 11172 213.6.231.32 (28 Feb 2001 06:31:43 GMT) Original-X-Complaints-To: usenet@quimby.gnus.org Original-NNTP-Posting-Date: 28 Feb 2001 06:31:43 GMT X-Public-Key: http://pgp5.ai.mit.edu:11371/pks/lookup?op=get&search=0x1B488DEA User-Agent: Gnus/5.090001 (Oort Gnus v0.01) Emacs/20.7 Precedence: list X-Majordomo: 1.94.jlt7 Original-Lines: 37 Xref: main.gmane.org gmane.emacs.gnus.general:35077 X-Report-Spam: http://spam.gmane.org/gmane.emacs.gnus.general:35077 > As the number of people with the same right hand side increases, > the risk of having a clash in the left hand side increases more > than linearly. (Not sure if it's exponentially.) Even though It's the birthday paradox, see for a good explanation. >>From : ======================================================================== CUT HERE - CUT HERE - CUT HERE - CUT HERE - CUT HERE - CUT HERE - CUT HE ======================================================================== N! Pd(N,s) = 1 - ------------ (N-s)! N^s where s is the expected number of samples needed, N the size of the population being sampled, and p the given probability. ======================================================================== CUT HERE - CUT HERE - CUT HERE - CUT HERE - CUT HERE - CUT HERE - CUT HE ======================================================================== A little bit later in the article is a approximation formula. A simple approximation formula for big N is sqrt( 2 * N ) for the 50% chance of having a collision. Best regards, cu, -cc- -- => GNU Emacs Webring @ <= Look Ma, this man can twist his fingers as if they were made of rubber, isn't that amazing? -- Not really, he's been using emacs for years...!