case folding [was: tuning ]

[David Relson]

At 12:32 PM 5/8/03, you wrote:

>The spambayes filter (spambayes.sourceforge.net) converts everything
>to lowercase except in the subject line.  According to their tests,
>the subject line is the only place where case made a significant difference.
>
>Most of their testing, however, was done with databases of up to 1000
>emails in each category.

Bob,

Bogofilter has an option to create special tokens (with a "subj:" prefix) 
from words in the Subject: line.  It's likely a small change to skip case 
folding for those tokens.

David