Random Data Compressed 100:1 (Guffaw)

[georgemw at speakeasy.net]

On 16 Jan 2002, at 18:23, Eric Cordian wrote:

> Seems our intrepid reporter has given Mr. Saint George, the ZeoSync CEO,
> his own writeup in Wired News.
> 
> http://www.wired.com/news/technology/0,1282,49599,00.html
> 
> Particularly interesting is the following claim...
> 
>   "What hasn't been previously proven, we're proving. We can compress
>    every single permutation of an N-member set. These are going to be the
>    details that we're going to be announcing in a few days."
> 
> Last I counted, there were N! permutations of an N-member set, and N^N
> sequences of N elements taken from an N-member set.  
> 
> For big N, and even moderately sized N, N! << N^N.
> 
> I hope Mr. Saint George hasn't spent the last 12 years of his life
> discovering that permutations are compressable. 
> 
> -- 
> Eric Michael Cordian 0+
> O:.T:.O:. Mathematical Munitions Division
> "Do What Thou Wilt Shall Be The Whole Of The Law"
> 
> 

Haven't checked the gzip site in a long time, but last time I did
there was some amusing stuff there.  The guy who wrote it
(gzip) mentioned that he had had to spend a lot more time
investigating patents than investigating compression techniques
(to make sure that gzip didn't step on any), as I recall he found
several differnt patents claiming to have algorithms for compressing
random data (which he quite rightly dismissed as the equivalent of
perpetual motion).

One (already patented) technique was essentially moving the data
from the file to the filename.  That is, I take a file called
"Readme.txt" with the info "Hello World", and I rename the
file as "Readme_Hello world.txt" and the file is now zero length!

I suspect the ZeoSync people are trying something similar.

George