
Google takes a lot of factors into consideration when trying to figure out where to place your website in their search engine results. Some of the factors are keyword and links; this is why there's a lot of emphasis on Keyword Research and Link Building in SEO. However the main topic today is pageranking, which is actually based on link building. Pagerank, which I've mentioned in a past post here, is an algorithm used by Google to assist their search engine result positioning (SERPs). It about placing numerical value on a particular web page based on number of internal and external links, maximum being 10 and minimum 0. There are a number of tools used to check google pagerank like this or that and SEOBook's toolbar. Now the thing is Google only updates it about every quarter, although Google has a slightly different internal pagerank causing the daily SERPs fluctuation. The bottom is always take the pagerank value with a pinch of salt.
The Pagerank for a website is calculated based on a number of factors (which nobody honestly knows, except Google), including do-follow incoming links, internal links, site popularity and other stuff. The pagerank for a given page is then distributed to all other external do-follow links on that particular page. For instance, take your home page, it has a page rank of 5, and 10 do-follow links are found on that page. That means pagerank or link juice given to those 10 links would be calculated as 10/5 = 2. If a no-follow link is found on that page, it won't pass an link juice to that page. Hence if you have lots of pages linking to you with high page ranks then they all add up to increase your own page rank, this also includes internal links. The reverse is also the case; If you link to a number of other pages, including internal and external pages, you reduce the amount of link juice which gets passed on to those other pages. It doesn't affect your own pagerank but the amount you can pass on. Of course there are other facts which prevent it from being so simple and easy, things which are unknown to people who do not work with Google.
Pagerank sculpting is the 'art' of building your websites such that only the relevant pages have do-follow attributes so as to 'sculpt' the flow of your link juice. Pages which are not relevant for the front page would have no-follow attributes. However, I see this as irrelevant if a website is well structured. A well structured website would be categorised such that the homepage would link to sub-pages/gateways which then link to further inner pages. This way the internal link juice flows in a hierarchical order. Some pages which need to be found on the home page but do not carried much value, like a 'sign-in' or 'register' pages can have a no-follow attribute which prevents the link juice being passed on to that page. The main pages would be indexed due to well organised site architecture and more link juice from the home page. These pages would then link to the inner pages and pass their own link juice and so on... Sort of like the diagram below.
A lot of people have seen pagerank sculpting as a black hat seo trick and say it doesn't work any more because the no-follow link juice is lost in the algorithm and not redistributed across do-follow links. In my opinion, I think it's really down to common sense. What are you sculpting your pagerank for? If you categorise your website properly in the first place, you won't need to do much sculpting because only the necessary pages would be found on your home page.
That's my take on pagerank and sculpting your pagerank. What about you? what are you opinions on this practise? Do you think its okay or is it black hat SEO? As usual please drop a comment to let me know your thoughts.
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