> > Sorry if this contribution is "newbie-like" as I'm not an expert > > in any kind of mathematical/analytical field, but... Just wanted > > to mention that my Sedgewick algorithms book goes into a bit of > > detail on why prime numbers should generate better distributed > > hash values using the modulo operator than powers-of-two... > > Mathematically, that is true. However, if you analyze the computational > aspects, the impact is not obvious, as you are decreasing collisions at the > cost of a more expensive hash generation algorithm. I'm not saying that it > definitely wouldn't pay off, but the answer is not obvious, and my belief is > that there would be a small net loss. Beliefs are fine, but if this is going to make a big difference either way in ruby, wouldn't a *test* be warranted?