Monday, January 29, 2007

Defusing the Googlebomb

A few days ago, Google made some changes to their ranking algorithms to reduce the practice of Googlebombing. A Google bomb is basically a prank to manipulate the ranking of pages in Google’s search engine. It involves getting a lot of people to put a link to a particular web page on their site with the anchor text they want associated with the web page.

For example, if I wanted a search for “basketball stud” to show my blog as the first result, I’d get as many people as I could to place a link on their website that looks like this:
<a href="">basketball stud</a>

Then when Google crawls the Web and sees a large number of links that look like this, they would begin to favor this page over the rest when users search for “basketball stud”.

One of the most famous Googlebombs involves a search for miserable failure. While this used to show George Bush’s web page first in the results, it now brings up more relevant results. Danny Sullivan has written a good article about this.

How did Google reduce the affects of Google bombs? They’re not giving particulars, but they have admitted it’s purely automated. My guess is they analyze several factors:
  1. When and where was the link first found? Possibly Google tracks the growth of particular links.
  2. Does the link make sense for the web page or website? A red flag might be raised when a website about hacking points to a government web page when none of the other links do.
  3. Is the target page actually "about" the anchor text? If the words "miserable failure" aren't on the target page, it could be a bomb.

If you’d really like to dig into this subject, here’s a master’s thesis on the topic.