On Wednesday 02 February 2005 03:38, Chuck Williams wrote: > Paul Elschot wrote: > > An alternative is to make sure all scores are bounded. > > Then the coordination factor can be implemented in the same bound > > while preserving the coordination order. > > If I understand this, I think more is required. My normalization > proposal from a couple months ago involved a boost-weighted > term-coverage normalization of the raw scores (i.e., based on coord's > that are boost-weighted). Raw scores would be bounded in [0.0, 1.0], > unlike now where they are unbounded. But one also needs a way to > recover from the just the score critical quality information like, for > example, whether or not all terms were matched. I was hoping to do this > by simple thresholding, e.g. achieve a property like "results with all > terms matched are always in [0.8, 1.0], and results missing a term > always have a score less than 0.8". I'm not certain whether or not that > property can be obtained, but feel confident that this would yield a > pretty good absolute quality measure in any event.
In case of scores bounded between 0 and b, this will do I think: b * (score/b + nrMatchers - 1) / maxNrMatchers Java's float has enough room to accommodate the extra log2(nrMatchers) bits from this. Regards, Paul Elschot. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
