How Accurate is SpamAssassin's Bayes implementation?

Wiki Markup\[http://plg.uwaterloo.ca/~gvcormac/spamcormack.html This paper\], by Gordon Cormack and Thomas Lynam of the University of Waterloo, details tests performed to measure accuracy rates of various open-source spam filters.

It compares the various modes of using SpamAssassin's Bayes implementation, then compares SpamAssassin's Bayes against other popular open source pure-learning spam filters (Bogofilter, Spambayes, SpamProbe, DSPAM, and CRM-114). SpamAssassin consistently does well, and is among the lowest in false positives (as of the July 1 2004 revision).

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