Google PageRank™

Google PageRank™


Please note that PageRank is currently being exported (starting late April, 2007). During this time you may see fluctuations between the old and the new PageRank score on your Google Toolbar, and occasionally PageRank may not appear at all. These shifts will eventually settle down as the new data replaces the old on all datacenters during the coming weeks.
The foundation of its system and trademark patent of Google, PageRank is one of the hundred or so factors that define the position of a web page for a given query. It is related to the number and importance of links pointing to a certain URL from other web sites, also an indication on how the internal navigation is laid out within the domain. Both Googlebot and users expect the page hierarchy of a web site being indicated by its metrics. PageRank may have become less important during the years of subsequent system updates, but is still a major factor. The best way to describe its use would be, that it is an indication of page importance or page weight within a set of relevant and trusted results. A page that is more important than another with all other parameters being the same, will naturally be shown first. However with TrustRank playing a major role in providing a better user experience, PageRank alone is not an indication of a page or a web site ranking higher than others. PageRank is based on but the amount of incoming links, references from important ( other high PageRank ) web sites, and the level of a page indicated by the internal navigation of a web site. Relevance and TrustRank are not indicated by this number.

Known issues


Case 1,
The PageRank that is published from the internal databases of Google usually has a 90 days refresh rate. It is a snapshot of what the PageRank of a single URL was at a certain time, which has been noted within about three months, thus is not real time information. While PageRank is being calculated to several decimals and updated constantly, the PageRank shown on the Google Toolbar will not show the current score. Thus a page with PageRank 0 shown may very well have a higher score than on the toolbar, and the opposite may happen as well, a high PageRank showing for certain pages may not indicate an already downgraded score, even if it has been decided in the background ( and has been calculated into displaying search results ). None the less it is still a good general indication for both page importance and in-site navigation layouts, and may be referred to as a factor when evaluating the weight of a URL.

+ Resolution: The only known area where public PageRank statistics are considered ahead of the PageRank in practice ( the unpublicized score ) is link trading, which is heavily advised against. Link exchanges that take place for the sole purpose of gaining PageRank will be seen as an attempt to manipulate search results, and thus be devalued, either automatically or during a manual evaluation. Domains that show irregular linking patterns or profiles, reference and are referenced by off-topic pages in an excessive amount, are being linked in great numbers from otherwise unvisited pages that were created to support their placement in Search Engines, and directories that don't use editorial evaluation when considering their listings are more often than not seen as manipulative practice.


Case 2,
Recently with the introduction of the reworked Supplemental Index, PageRank again became important in analyzing a web site's navigation funnels. If due to the internal linking of the pages, some are perceived less important than others ( are too many links away from the home page, are being linked to with irrelevant anchor text or no anchor text at all, are not being linked to in the expected amount to raise their in-site importance ) and thus gain less PageRank, they may become tagged as Supplemental Results. A low PageRank score ( 0 ) may indicate that the source of the problem is in the way these pages are referenced to within the web site ( unless of course the URL in question has been created after the last export of PageRank data, or the page has accumulated quality links since the calculation of its score currently showing ). Read more on Supplemental Results and Website Navigation.

+ Resolution: To achieve a medium or high PageRank, you need your web site to accumulate "natural", quality inbound links from other web sites. If the pages are popular, and are supported by a lot of references from other locations, and especially if important ( high PageRank ) web sites link to them, their score will increase naturally. Note again that despite its name, PageRank is not the only factor that decides how the page will be positioned on the search results. Also note that Google analysts have recorded and calculated many patterns of irregular linking behavior, and the algorithms can, with good accuracy, detect which references are not "natural". Such links are typically the ones that have been purchased or negotiated for the sole purpose of acquiring PageRank. A good indication on what to avoid if you see links that entirely disregard usability or user experience, are off-topic and probably would not be clicked on, and in general appear to be less aimed at visitors and more as an attempt to haste the accumulation of PageRank. Such links are often discarded, and in certain cases, or if the volume of such links is exceeding what could be seen as accidental, penalties could follow for either or both the source and the target URLs. See more in Link Schemes.


Case 3,
For pages within the same web site, PageRank is a good indication of linking hierarchy. A certain amount of PageRank is passed on from the home page to level one pages, for example categories, or sub-pages, then these pages again pass some of the importance to the resources they link to. Same level pages, in other words, pages that are an equal number of links away from the home page and/or are linked to in equal numbers within the domain, will share the same score. Thus planning the website navigation is of key importance when indicating what information you consider the most unique and useful, what pages you believe offer enough choice, but also enough information to your visitors as the first or second screen to be seen.

+ Resolution: Cross linking same level pages is important, however unrealistic navigation, such as hundreds or even thousands of links on every page are strongly advised against. Trying to communicate the message of all being tier one, will most likely be held up for further examination by anti-spam filters. Stay reasonable with such cross-linking. Read more on Website Navigation.


Case 4,
PageRank history and "natural" links: The system of PageRank was designed to evaluate a web site's importance during a period of the Internet when links would serve the sole purpose ( and were the single source ) of allowing a visitor to follow up on a certain topic. Web sites that were often referred to, were with a good chance the most valued resources for the information, thus were seen as the best choice and ranked highest in the search results. A revolutionary idea at the time, that since then became the target of spammers as soon as marketing through organic search results became a widespread practice. PageRank by itself was no more a viable source of information on the value of a web page. For years, the cross examination of user and web site behavior, link analysis and linking behavior patterns have been used to fine-tune search engines, including Google, which can now tell whether a link was meant for the users ( and in the same time increase the importance of a page ), or was added for the sole reason to cast a vote for a web site through the link popularity system. Too much of the latter will trigger closer examination, discarding of these votes, and sometimes a penalty or ban.