Neil wrote:
> I'm wondering about the best way to train my Bayes filter (per-user
> filtering).
>
> I have a Junk folder, and it contains roughly three categories of mail
> (to my mind, at least):
> A. Mail SpamAssassin marked spam and auto-learned as spam.
> B. Mail SpamAssassin marked spam, but did not autolearn.
> C. Mail SpamAssassin did not mark spam, which I moved in there.
>
> So my questions:
> 1. Would it be bad for me to just run sa-learn on the entire Junk
> folder; or should I just let auto-learn do it's thing and sa-learn the
> false negatives?

No. It's not bad.

If SA has already correctly learned the message, it will be skipped. Of
course, this means it's a waste of time to feed SA messages it's already
learned correctly, but it's not going to hurt anything.

>
> 2. Likewise, my Inbox contains just ham; could I run sa-learn on that
> entire mailbox periodically?

Ditto.
>
> 3. Lastly, will it be detrimental (in terms of future accuracy) to
> sa-learn the same mail more than once, or will SpamAssassin remember
> it? (I seem to remember reading the latter, but I wasn't sure).

It will remember
> If it does, how long/many previous mails does it remember?

Currently the bayes_seen mechanism has no expiration, so it will
remember forever, or until you manually delete bayes_seen.