1. The first place to start reading is "How POPFile does email classification" which you can find here: http://sourceforge.net/docman/display_doc.php?docid=13334&group_id=63137
2. Then read "Bayes Theorem and Logarithms" which you can find here: https://sourceforge.net/docman/display_doc.php?docid=13648&group_id=63137
Those two documennts give a general overview...
