If you want a general algorithm that will handle all kinds of possibilities - then you want something that is ignorant of the actual content and instead does statistical analysis on what it "sees"

In other words, you want Bayesian analysis done over a structure similar (if not exactly) like a Markov Matrix.

But if you are going to do that - be warned that you are repeating the work of the very successful SpamAssassin.
(I've used spamassassin for awhile now and it kicks ass for spam)

If you are writing something just as a programming exercise, then look into that - if you are writing it to solve your spam problem - then I would first look into SpamAssassin.

-------------------------------------------------------------------
There are some odd things afoot now, in the Villa Straylight.

In reply to Re: Spam filtering regexp - keyword countermeasure countermeasure by AssFace
in thread Spam filtering regexp - keyword countermeasure countermeasure by John M. Dlugosz

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.