Month: September 2007

Google Page Rank and the Heisenberg Uncertainty Principle

There is trouble in Google Land… Things are afoot, the Google tool bar page rank hasn’t been updated for months. Several big directories are finding their position in Google wobbling, site positions on the results page are bouncing up and down and there is talk that Google will remove the public page rank information displayed on its tool bar.

This has led to blog posts about new major algo changes coming from Google and posts in forums about how would we be affected by Google removing the page rank. In all of this I have been thinking about the Google Page Rank and how it is self influencing.

The Heisenberg Uncertainty Principle is sometimes represented as “whatever you study, you also change” and although this is more accurately called the observer principle for this blog post it will do.

Page rank uses a ballot system where a link from page A to page B is a vote, by page A, for page B. Combined with analysis of the page that casts the vote, page rank determines which votes weigh more heavily and help to make other pages “important”. Underlining all this is the principle of determining the likelihood that a person randomly clicking on links will arrive at any particular page.

It is the use of probability in determining the likeihood of randomly find a page which also makes page rank self influencing. If Google didn’t exist then the ideas behind page rank would be true, however the very existence of the Google search engine has disrupted the likeihood of finding a page randomly and so it has disrupted the page rank.

Today large portions of traffic to web sites comes from people clicking on the results from a Google search. If I am looking for reviews of a certain car brand, I will type in a search into Google and follow the links presented to me. If I like a page I see, maybe I will bookmark it or even blog about it or maybe include a link on my website. The result is that because I found a page on the search engine (based partly on its page rank) I then added a link to that page and thus increased its page rank by casting another vote for that site.

This means that pages placed at the top of the results pages have a greater chance of gaining more links to themselves. By trying to measure the importance of a web page, Google have in fact changed the importance of that web page and so the Heisenberg Uncertainty Principle becomes true of page rank.

QED

Gary