[Mailman-Developers] Anti-spam "killer app"?

[Satya]

Sounds very cool and usable. I've started hacking up a Perl (please
don't deactivate me!) thingy which'll be called from procmail, and
another perl thingy which'll be called from crontab ... well, never
mind the details.

I'm stuck on the Bayesian probability thing. What is what?

           Pr{X and Y}
Pr{Y|X} = -------------
             Pr{X}
 

is what's at http://www.mathpages.com/home/kmath143.htm but what is X
and Y, and how do I ... oh never mind, the question is too
complicated.

P(y/x) = probability that this is spam given that the word we're
looking at is a spamword? Then what is P(xy)? Is it the probability
that the word is a spamword? Then what's P(x)?

And how do I accumulate the probabilities?

-- 
Satya. <URL:http://satya.virtualave.net/>
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