Bill Slawski has written up another interesting piece about how search engines substitute other search terms for yours depending on past user behavior. Of course, this is related to a patent he discovered that was filed by Yahoo.
Bill explains how this works:
Let’s say that a large number of people who search for the term intellectual property then go on to search for the term patent attorney with their very next search, or within the same search session.
The search engine log files would uncover that such an association exists, and the search engine might explore how common it is for searchers to search for that second phrase. If it happens frequently enough, the search engine may start suggesting patent attorney as a suggested search to searchers along with a display of search results for the term intellectual property.
Therefore, it's important to take these other substitutions into consideration when optimizing your page, according to a Cre8asite Forums post. It is helpful to look at the various suggestions and optimize accordingly.
Forum discussion continues at Cre8asite Forums.