Re: [libreoffice-users] Benford's Law

On 07/14/2013 05:01 PM, Toki Kantoor wrote:
> On 07/13/2013 11:01 PM, Brian Barker wrote:
>
> > Unless I misunderstand,the formula =10^RAND() should create random variates in the range (1,10) 
> > following the law.
>
> 10^RAND generates a set of random numbers that does _not_ adhere to
> Benford's Law.  I need a random number generator whose output does
> adhere to Benford's Law.
>
> jonathon

Hey Jonathon,

This is the distribution I got after 100 million cycles:
10^RAND

9 - 0.045
8 - 0.051
7 - 0.057
6 - 0.066
5 - 0.079
4 - 0.096
3 - 0.124
2 - 0.176
1 - 0.300

I don't think you are going to get any closer to Benford's law 
distribution than that.

Here is the code I used:

use strict;
use warnings;

my $num;
my $lpcnt;
my @Distribution;
$Distribution[0]=0;

srand;

$lpcnt = 100000000;
while ($lpcnt) {
        $num=substr(10**rand(),0,1);
        ++$Distribution[$num];
        --$lpcnt;
}

$lpcnt = 9;
while ($lpcnt) {
        print "$lpcnt - ".substr($Distribution[$lpcnt]/100000000,0,5)."\n";
        --$lpcnt;
}


--
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   ^ ^  Mark LaPierre
Registered Linux user No #267004
https://linuxcounter.net/
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