Mail::SpamAssassin::Plugin::AutoLearnThreshold - threshold-based
discriminator for Bayes auto-learning
This plugin implements the threshold-based auto-learning discriminator
for SpamAssassin's Bayes subsystem. Auto-learning is a mechanism
whereby high-scoring mails (or low-scoring mails, for non-spam) are fed
into its learning systems without user intervention, during scanning.
Note that certain tests are ignored when determining whether a message
should be trained upon:
· rules with tflags set to 'learn' (the Bayesian rules)
· rules with tflags set to 'userconf' (user configuration)
· rules with tflags set to 'noautolearn'
Also note that auto-learning occurs using scores from either scoreset 0
or 1, depending on what scoreset is used during message check. It is
likely that the message check and auto-learn scores will be different.
The following configuration settings are used to control auto-learning:
bayes_auto_learn_threshold_nonspam n.nn (default: 0.1)
The score threshold below which a mail has to score, to be fed into
SpamAssassin's learning systems automatically as a non-spam
bayes_auto_learn_threshold_spam n.nn (default: 12.0)
The score threshold above which a mail has to score, to be fed into
SpamAssassin's learning systems automatically as a spam message.
Note: SpamAssassin requires at least 3 points from the header, and
3 points from the body to auto-learn as spam. Therefore, the
minimum working value for this option is 6.
If the test option autolearn_force is set, the minimum value will
remain at 6 points but there is no requirement that the points come
from body and header rules. This option is useful for autolearning
with rules that are considered to be extremely safe indicators of
the spaminess of a message.
bayes_auto_learn_on_error (0 | 1) (default: 0)
With "bayes_auto_learn_on_error" off, autolearning will be
performed even if bayes classifier already agrees with the new
classification (i.e. yielded BAYES_00 for what we are now trying
to teach it as ham, or yielded BAYES_99 for spam). This is a
traditional setting, the default was chosen to retain backward
With "bayes_auto_learn_on_error" turned on, autolearning will be
performed only when a bayes classifier had a different opinion from
what the autolearner is now trying to teach it (i.e. it made an
error in judgement). This strategy may or may not produce better
future classifications, but usually works very well, while also
preventing unnecessary overlearning and slows down database growth.
perl v5.20.1 Mail::SpamAssassin::Plugin::AutoLearnThreshold(3pm)