Thursday, April 15, 2010

Benford's Law

I heard about this crazy law at work the other day. This law explains that most numbers found in nature start with a 1, 2, or 3 than a 7, 8, or 9. It took me a while to understand this, but once I did, I was amazed. This means that numbers from street addresses, credit card bills, weather patterns, and height of buildings are more likely to start with a 6 than a 7, and even more likely to start with a 1 or 2.

This graph shows the likelihood of the first number being a specific digit.
 
The reason for this is pretty complicated. It has to do with logarithmic growth. Some experts can use this law to detect fraud. For instance, if someone is making up numbers in a bank account or some tax returns they would tend to make sure the numbers are equally random. If they see there are an equal amount of numbers starting with a 9 and a 1, this numbers are most likely false. Crazy, huh?
 

1 comment:

Bryan said...

I messed up the posting thing. This was supposed to show up this morning.