spam-prevention - SpamAssassin 如何定义 BAYES_99 ？如何避免？

Question

SpamAssassin 用原因 BAYES_99 标记我的电子邮件，这意味着该电子邮件是 99% ~ 100% 的垃圾邮件。SpamAssassin 检测这条规则的机制是什么（通过关键字？），我怎样才能避免碰到这条规则？

Answer 1

我发现这个是因为我使用 SendGrid 处理事务性邮件，而 sendgrid 正在从一个因发送其他人的垃圾邮件而被黑洞的服务器发送我的邮件。因为IP被黑洞，我的邮件被标记为垃圾邮件。诊断：

您可以在这里查看您的域或 IP 是否被列入黑名单： https ://mxtoolbox.com/blacklists.aspx

解决方法是切换到不同的电子邮件传输提供商。

Answer 2

BAYES_99 is a statistical component of SpamAssasin. It is using some sort/variation of Naive Bayes which has (to keep it simple) some sort of probability saying that some word/token is likely to be spam or not to be spam.

In "math" these could be expressed like this:

P(Class_Spam | Email)
P(NotClass_Spam | Email)

Transformations lead to e.g. this equation:

However there a lots of different representations of bayes classifiers. With different optimizations and statistical models.

You may disable it via spamassasin configuration. This question is not well placed on stackoverflow. Superuser would be the better fit though.