Google Page Rank- mythbusting
Recently I am seeing a lot of content on the web- by nouveau SEO guys, Public Relations professionals and even web developers on how PageRank might be a useless metric to look at.
Many people say that like Tehnorati Authority- PageRank is dead. Well frankly, Technorati Authority diminished in importance to me some time back. Specially in the Asian context- even for English language blogs- it is not a very useful criterion to look at. Maybe that will change with their re-found focus, but as of now- it is clumsy, not widely adopted and just not suited for the Asian context.
However, PageRank is different.
It might have lost some importance – or rather, ‘corrected’ in perception over the past year. Even Google lately removed it from its list of webmaster tools- stating that people obsess over it too much (perhaps without understanding it much). Clear signals have been sent that PageRank does not singularly impact your SERPs (Search Rankings).
Understand that there are allegedly about 200+ parameters that Google takes into account while evaluating your search rankings. PageRank is one of them.
Then why do I think it is not entirely useless? First of all- it is important to understand in all its simplicity that PageRank defines the incoming links to a page. Every incoming link is a citation and the more the citations, better is the possibility that your content is relevant.
But more than, PageRank also assigns weightage to links. All incoming links are not treated equal. The value of that link also depends on the Page Rank of that web page sending the link itself.
“PageRank also considers the importance of each page that casts a vote, as votes from some pages are considered to have greater value, thus giving the linked page greater value. We have always taken a pragmatic approach to help improve search quality and create useful products, and our technology uses the collective intelligence of the web to determine a page’s importance”
To calculate the PageRank for a page, all of its inbound links are taken into account. These are links from within the site and links from outside the site.
PR(A) = (1-d) + d(PR(t1)/C(t1) + … + PR(tn)/C(tn))
That’s the equation that calculates a page’s PageRank. It’s the original one that was published when PageRank was being developed, and it is probable that Google uses a variation of it but they aren’t telling us what it is. It doesn’t matter though, as this equation is good enough.
In the equation ‘t1 – tn’ are pages linking to page A, ‘C’ is the number of outbound links that a page has and ‘d’ is a damping factor, usually set to 0.85.
We can think of it in a simpler way:-
a page’s PageRank = 0.15 + 0.85 * (a “share” of the PageRank of every page that links to it)
“share” = the linking page’s PageRank divided by the number of outbound links on the page.
A page “votes” an amount of PageRank onto each page that it links to. The amount of PageRank that it has to vote with is a little less than its own PageRank value (its own value * 0.85). This value is shared equally between all the pages that it links to.
So if you were a scammer- willing to put that effort into creating web pages pages having a high rank themselves, it might be too much work. And there is always the risk that sooner than later, it will be discovered. Even if it does not result in getting banned, it will have zero benefit at the minimum- for all that effort.
It is important to notice that there are other attributes that Google uses to identify relevance- interesting ones being age of domains, IPs of incoming links (are they the same as your web site) , On page elements, etc. As I mentioned earlier- 200+ criterion.
PageRank does not seem to take into account anything else other than the number and ‘weight-age’ of the incoming links. It clearly says that things like your content (and frequency of update etc) are not a part of Pagerank calculation. Of course these things matter for overall SERPs- but for PageRank calculation- they do not.
Similarly, there is evidence to say that a wikipedia or a dmoz, yahoo directory link or a .edu or .org domain inLink does not impact pageRank; contrary to popular opinion. It does to your overall SERPs maybe- but not to PageRank.
So the thing worth keeping in mind: PageRank is not just a total count of incoming links (Yahoo incidentally is favored for a closer match to that count- amongst professionals)- but includes weightage of links too.
What’s more- PageRank is not a flat number of random ranking. The original score is corrected on a logarithmic scale to fit a scoring range of 0-10. This also brings to the forth- another interesting observation.
When comparing different pages on the web on the basis of PageRank, it is important to note that the ‘point’ difference is not simply the difference of the higher and the lower number. If you have a PageRank of 5- does not mean you are just, 1 point or 1% or 10% better than someone with a PageRank 4- every percentage point implies a significant difference by itself. So a Site with PageRank of 5 will have significantly higher value than another one of say PageRank 3. And the one with PageRank7 will be significantly significantly higher than PageRank 4.
To me this metric imparts value to relevant content. Not just widely reached or widely linked back to- but I’m saying that every link does not have equal weightage. That itself is an important thing.
I agree that the criterion to impart weightage/value is not great- but at least it gives context relevance to the links. And even to those pages that are linking back to you.
What does that mean to you? Further explanation-
- If you get a linkback from a page that had PageRank 6 Vs a page that had PageRank 4- you get more weightage from the former link. Keeping in mind the next point-
- If you get linkback from a page with high pagerank but high number of outgoing links, the impact of each outgoing link diminishes in value.
- So as an example- If you get links from a site with 100 Outgoing links and PageRank 6- Versus a site that had, say 10 outgoing links and PageRank 4, you will get more weightage from the latter
And worth repeating: PR alone is not the factor that will get you front page exposure; however, it does provide a measure of the value of your website. Some people (Google-Matt Cutts- Head of Webspam team himself) say that even if PR is not the only thing you have to worry about, it still determines how often and how deep google crawl your website for updates, which is important if you update your content often.
On the web today- one thing is clear- you cannot have obsessive focus on one metric or tool. In the state it is today, you need to consider multiple factors. And so you need to clearly understand those multiple factors.
Page Rank is one of them- and probably one of the most misunderstood.
Think about it