11. PR0 - Google's PageRank 0 Penalty

By the end of 2001, the Google search engine introduced a new kind of penalty for websites that use questionable search engine optimization tactics: A PageRank of 0. In search engine optimization forums it is called PR0 and this term shall also be used here. Characteristically for PR0 is that all or at least a lot of pages of a website show a PageRank of 0 in the Google Toolbar,

even if they do have high quality inbound links. Those pages are not completely removed from the index but they are always at the end of search results and, thus, they are hardly to be found.

	A PageRank of 0 does not always mean a penalty. Sometimes, websites which seam to be penalized simply lack inbound links with an sufficiently high PageRank. But if pages of a website which have formerly

We can do nothing but speculate about the causes for PR0 because Google representatives rarely publish new information on Google's algorithms. But, non the less, we want to give a theoretical approach for the way PR0 may work because of its serious effects on search engine optimization.

The Background of PR0

Spam has always been one of the biggest problems that search engines had to deal with. When spam is detected by search engines, the usual proceeding is the banishment of those pages, websites, domains or even IP addresses from the index. But, removing websites manually from the index always means a large assignment of personnel. This causes costs and definitely runs contrary to Google's scalability goals. So, it appears to be necessary to filter spam automatically.

Filtering spam automatically carries the risk of penalizing innocent webmasters and, hence, the filters have to react rather sensibly on potential spam. But then, a lot of spam can pass the filters and some additional measures may be necessary. In order to filter spam effectively, it might be useful to take a look at links.

That Google uses link analysis in order to detect spam has been confirmed more or less clearly in WebmasterWorld's Google News Forum by a Google employee who posts as "GoogleGuy". Over and over again, he advises webmasters to avoid "linking to bad neighbourhoods". In the following, we want to specify the "linking to bad neighbourhoods" and, to become more precisely, we want to discuss how an identification of spam can be realized by the analysis of link structures. In particular, it shall be shown how entire networks of spam pages, which may even be located on a lot of different domains, can be detected.

11. PR0 - Google's PageRank 0 Penalty (continued)

This article reproduced with permission of eFactory.
© 2002 eFactory Internet-Agentur KG Online-Marketing - written by Markus Sobek
PageRank and Google are trademarks of Google Inc., Mountain ViewCA, USA.
PageRank is protected by US Patent 6,285,999.