On Fri, Jul 17, 2009 at 01:37:43PM -0500, travis+ml-cryptogra...@subspacefield.org wrote: > I'm curious if there's a way to express this calculation as a > mathematical formula, rather than an algorithm, but right now I'm just > blanking on how I could do it.

This has been dubbed the "guesswork" of a distribution by some authors, I think originating with: John O. Pliam. The disparity between work and entropy in cryptology. http://philby.ucsd.edu/cryptolib/1998/98-24.html, February 1999 It turns out that its asymoptic behaviour is bit like that of Renyi entropy, see: E. Arikan. An inequality on guessing and its application to sequential decoding. IEEE Transactions on Information Theory, 42:99105, Janurary 1996. I did an explanitory writeup of this with some experiments at: http://www.maths.tcd.ie/~dwmalone/p/itt05.pdf David. --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com