 tp tim peters tim one comcast net writes tp jeremy hylton the total collections are NUMBER messages i trained with NUMBER NUMBER messages tp i m reading this now as that you trained on about NUMBER spam and tp about NUMBER ham that s less than NUMBER of the sizes of the tp training sets i ve been using please try an experiment train tp on NUMBER of each and test once against the other NUMBER of each this helps a lot here are results with the stock tokenizer training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER total false pos NUMBER NUMBER NUMBER total false neg NUMBER NUMBER NUMBER and results from the tokenizer that looks at all headers except date received and x from_ training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER training on mbox home jeremy mail inbox NUMBER mbox home jeremy mail spam NUMBER NUMBER hams NUMBER spams NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER total false pos NUMBER NUMBER NUMBER total false neg NUMBER NUMBER NUMBER is it safe to conclude that avoiding any cleverness with headers is a good thing tp do that a few times making a random split each time it won t be tp long until you discover why directories of individual files are tp a lot easier to work e g random shuffle makes this kind tp of thing trivial for me you haven t looked at URL have you i m using random shuffle too you don t need to have many files to make an arbitrary selection of messages from an mbox i ll report some more results when they re done jeremy 