[Spambayes] A little idea

Gary Robinson grobinson@transpose.com
Sat, 21 Sep 2002 17:16:38 -0400

```One small idea...

We all recognize that middling values are less important, but that is
implicitly recognized by the multiplicative math we are doing.

NEVERTHELESS, since we are not being purist, I think it would be fun to try
one simple modification.

We are trying different max_discriminator values which represent a binary
choice... a p is either IN or OUT. But wouldn't it be logical to be more
gentle about it, and just weight them less as they become more middling?

So the idea is to weight each p by c(w)=2*abs(.5-p(w)) (it's nice to have
weights that vary between 0 and 1).

When you're multiplying and taking the nth root, this is done by using the
weights as powers and using the sum of the weights as the root: So when we

((p(w1)^c(w1))*(p(w2)^c(w2))*...*(pwn)^c(wn))^(1/(c(w1)+c(w2)+...+c(wn)).

This looks a little more natural when you do the calcs using logs, because
then you just multiply each term by the weight rather than using it as a
power... but the result is the same either way.

Just a thought!

--Gary

--
Gary Robinson
CEO
Transpose, LLC
grobinson@transpose.com
207-942-3463
http://www.emergentmusic.com