On Fri, Oct 15, 2010 at 10:05 AM, Phil Bewig <pbe...@gmail.com> wrote: > Not quite. > Random numbers are uniformly distributed, so the first digits of a set of > random numbers should all appear equally. > Benford's Law most often applies to sets of naturally-occurring numbers that > are scale-invariant. Consider the lengths of rivers, as Benford did. It > doesn't matter whether the rivers are measured in miles or kilometers > (scale-invariant). The first digits of the lengths of the rivers will > conform to Benford's Law, as long as the set has enough elements. > Auditors use Benford's Law to find anomalous records. Apply Benford's Law > to a list of the amounts of all checks written by a company in the last > year. If you see too many checks that start with the digits 7, 8, or 9, > there is a clear indication of fraud. The embezzler wrote checks that were > slightly less than $1000, on the theory that small checks would more likely > be ignored. But instead of writing checks for $263 or $347 or $519, he > wrote checks for $838 or $922 to maximize his payout. > There was an external audit of the voting results in last year's Iranian > elections. The audit clearly showed fraud, as there were far too many > precinct tallies that started with the digits 8 or 9.
I just love seeing real useful application of seemingly abstract math concepts... :) _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
