Mail::SpamAssassin::Bayes - determine spammishness using a Bayesian classifier

This is a Bayesian-like form of probability-analysis classification, using an
algorithm based on the one detailed in Paul Graham's *A Plan For Spam* paper
at:

http://www.paulgraham.com/spam.html

It also incorporates some other aspects taken from Graham Robinson's webpage on the subject at:

http://radio.weblogs.com/0101454/stories/2002/09/16/spamDetection.html

And the chi-square probability combiner as described here:

http://www.linuxjournal.com/print.php?sid=6467

The results are incorporated into SpamAssassin as the BAYES_* rules.