The Auto-Whitelist
Introducion
The auto-whitelist, or AWL, tracks scores for your regular correspondents in a small on-disk database. It is enabled using the -a flag to spamassassin or spamd.
...
Sometimes it may appear that the AWL is assigning scores the wrong way; read AwlWrongWay for details.
How Does It Work?
The algorithm works using a database of entries. Each entry has a key formed by the From: address of the mail, and the IP address it originated at, and contains a TOTAL score and a COUNT number. The MEAN score is TOTAL/COUNT. The current algorithm works as follows:
...