| In the SEO realm there is a lot of attention paid to PageRank as an indicator of a domain's SEO value. Although it is one of the most important aspects of a domain's value in the eyes of Google, there are a few points that should be mentioned.
Google assigns each page on the web a weight and when one page links to another it passes some score onto the page it is linking to. First of all, for whose who don't know what PageRank is - it is a value used by Google to decide how important a domain is based on analysis of link on the internet. Web pages that don't have any PageRank are often symbolised as having N/A PageRank.The higher the PageRank, the more likely Google is to trust it. Google PageRank has 11 scores, between 1 and 10. This is true for both external and internal links.
A site can have a high PageRank with relatively few links pointing to it if those links are of a high PageRank.The most important factor in the distribution of PageRank to a web page is the PageRank of the pages linking to it. So, if a web page has 4 PageRank 4 and 3 PageRank 3 links pointing at it, it will probably be assigned a PageRank of 4. The higher the PageRank of pages linking to a given page, the higher its PageRank is likely to be. PageRank is generally not assigned to a page higher than the pages that link to it. Also, pages that have a lot of low PageRank and PageRank N/A hyperlinks pointing to them can have their PageRank reduced as a result. Sheer quantity of links does not help to increase PageRank.
Some suggest that the text content of the page affects PageRank assignment, but this doesn't seem to be the case. There is no substantiated evidence that text affects PageRank other than pages that have been spammed often have their PageRank removed.
When it come to sub-pages, time is a factor in PageRank distribution. When new sites first get assigned PageRank their sub-pages often remain without any PageRank. In general, sub-pages are a little slow to get assigned PageRank. Google is generally less trusting of sub-pages unless they belong to a trusted domain. In particular websites with a lot of sub-pages and even more so sites that link to a lot of internal pages (like directories) can struggle to pass their PageRank to internal pages.
The structure of the site has a major role to play in the assignment of PageRank. Google uses what is known as block level analysis to analyses web pages. They use their knowledge of the nature of the web to decide what links on a page are probably the most trustworthy and the pages these links point to are more likely to be assigned PageRank.
Google can and do change websites' PageRank. This is generally as a penalty for sites that have used unhonest practices. This can often cause all the site's sub-pages to loose their PageRank. It has also been claimed that in the past Google has made mistakes in PageRank distribution.
Lastly, the PageRank of a web page may change even though there has been no change in the hyperlinks pointing to that page. This is either due to changes in the structure of links between all websites or adjustments made by Google.
Sky Alfaro is an SEO consultant with the SEM Labs SEO Agency where she helps small to medium sized companies with search engine marketing training. |
