Date: 08/06/98 at 18:19:53 From: Elisabeth Edwards Subject: Benford's Law What is Benford's law? I heard about this law in the newspaper and am curious about it.
Date: 08/13/98 at 13:50:23 From: Doctor Benway Subject: Re: Benford's Law Hi Elisabeth, I found the following information about Benford's Law at this website: http://mathworld.wolfram.com/BenfordsLaw.html Benford's Law "Also called the First Digit Law, First Digit Phenomenon, or Leading Digit Phenomenon. In listings, tables of statistics, etc., the Digit 1 tends to occur with Probability approximately 30%, much greater than the expected 10%. This can be observed, for instance, by examining tables of Logarithms and noting that the first pages are much more worn and smudged than later pages. The table below, taken from Benford (1938), shows the distribution of first digits taken from several disparate sources. Of the 54 million real constants in Plouffe's Inverse Symbolic Calculator database, 30% begin with the Digit 1." In other words when you have tables of numbers, the digit "1" occurs more often than any of the other numbers do. The Web site also shows a few examples of where this happens. If you're interested in learning more about this, I suggest checking out the site. For more information, see Kevin Brown's MathPages (under Probability and Statistics): Benford's Law http://www.mathpages.com/home/kmath302/kmath302.htm and Peter Wolfenden's page: The Significant Digit Phenomenon, AKA Benford's Law http://www.wolfendens.com/digit.html - Doctor Benway, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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