What is a Bayesian filter? What does SpamBully's Bayesian filter analyze?

A Bayesian filter is a type of spam filter that looks at the probabilities of words and html tags that appear in an email message.  If the message is a spam message, it will increase the rank of the words in its dictionary.  If it is a good message, it will decrease the rank of the words in its dictionary.  By doing this over thousands of messages certain words and patterns emerge that distinguish your good emails from your spam emails.  In general, this works much better than standard message rules because the Bayesian filter can pick up on many underlying parameters that a user will miss.  It is also able to adapt quickly to new types of spam emails without a user having to spend time writing a new message rules everytime a new spam comes in.

SpamBully's Bayesian filter analyzes words and html tags in the body of the html message and also analyzes the subject and headers. 

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