Questions On PR

[ctabuk]

Here in the SEO forum we still get a lot of questions relating to Google Page Rank and what it is and how it works.
In case you have not read this please do
www.webproworld.com/viewtopic.php?t=25934&start=0

[IIxxVADERxxII]

Do you have access to your traffic logs for google traffic? Would this site hurt from a loss of google traffic?

[mike21]

Here is how we explained PageRank in in our link building research paper:


The concept

Basically, PageRank(PR) determines your page’s importance by finding out how many other pages link to your page and the relative importance of those linking pages. Each link to your page by another page is considered a vote by the linking page for your page. The weight or value of the vote is determined by the importance of the page that links to yours.

Google assigns every webpage a PageRank number ranging from 0 to 10. You can check the PageRank value of every page you visit by downloading the Google Toolbar.

The exact way in which PR is calculated is a google secret, but all specialists agree that the scale is algorithmic, which means that one link from a PR 5 site will boost your own PR more than 100 links from PR 2 sites.

Besides the PR score, the quantity of outbound links on the page linking to your page is important as well. In general, the more outbound links there are on the linking page, the smaller the PR boost that your page will receive from the link. For example, a link from a page with a PR of 5 that has 100 outbound links on it will boost your page’s PR less than a PR5 page containing only 10 outbound links.



Pagerank in the past

A few years ago, PR was the dominant factor in ranking pages for a search. Given two sites with relatively equal content, the one with the higher PR virtually always had a better search engine ranking. As every link does in fact boost your PR (no matter how artificial it is), it was quite easy to manipulate google’s search results. By simply buying a few text links from high PR sites, every webmaster could buy him or herself a top search engine ranking.


That is why google has significantly reduced the importance of Pagerank. Now several other factors determine the value of a link. For example, relevancy. A link from a relevant PR 3 site can be more valuable than a link from an irrelevant PR 5 site.

Pagerank’s importance

Pagerank, though, still has a certain importance. Important, authoritative websites virtually always have a high Pagerank, and a link from them is highly valuable. The problem is that websites considered unimportant or even bad by google can also have a high PR, due to artifical link building. A link from those sites won’t improve your search engine ranking at all.

If a certain website has a PR of 0, it is either new or it has been banned by google due to search engine spamming. You should never link to those sites, as this can result in your site being penalized as well (linking to a bad neighborhood).

Moreover, as above-mentioned, many webmasters look at PR when considering linking to another site. Even if you have a site with great content, other websites might refuse linking to you if you have a PR lower than 3 or 4.

A relatively easy way to acquire a certain level of PR is by submitting your websites to directories, which will subsequently be discussed in the following chapter.

[kgun]

The exact way in which PR is calculated is a google secret, but all specialists agree that the scale is algorithmic, which means that one link from a PR 5 site will boost your own PR more than 100 links from PR 2 sites.
following chapter.

Good post, but I think you mix SERP ranking and Google Pagerank (http://www-db.stanford.edu/~backrub/google.html) (section 2.1.1) that is no secret as far as I know. There are a lot of third party page rank calculators, and I have not seen any that gives a different result from Google's.


We assume page A has pages T1...Tn which point to it (i.e., are citations). The parameter d is a damping factor which can be set between 0 and 1. We usually set d to 0.85. There are more details about d in the next section. Also C(A) is defined as the number of links going out of page A. The PageRank of a page A is given as follows:
PR(A) = (1-d) + d (PR(T1)/C(T1) + ... + PR(Tn)/C(Tn))

Note that the PageRanks form a probability distribution over web pages, so the sum of all web pages' PageRanks will be one.

PageRank or PR(A) can be calculated using a simple iterative algorithm, and corresponds to the principal eigenvector of the normalized link matrix of the web. Also, a PageRank for 26 million web pages can be computed in a few hours on a medium size workstation. There are many other details which are beyond the scope of this paper.
Source: http://www-db.stanford.edu/~backrub/google.html

Example:
http://www.google-pagerank.net/

Related link:
http://pr.efactory.de/ (easier to understand for non mathematicians).

I think it started here:
http://www-group.slac.stanford.edu/acd/Resources.html

These are excellent tools:
http://www.marketleap.com/
http://www.googlerankings.com/

[dannywirken]

Is there a list that has been calculated as an example:


X amount of PR2 sites will get you PR5
X amount of PR3 sites will get you PR5

etc....

[charlierobot]

I have many of my clients who are convinced that if they buy a permenant link on a PR 5 - 7 website that they will also get a higher pagerank in the next update. They also see that this will get more traffic because of this as well.

Well I have seen customers try both and received little in return. I advise clients to stick to their link neighbourhoods write good content and use keyword based anchors - this worked for over 30 of my clients in the last Google update where 10 went from 0 - 3 in Pagerank.

[imported__sam_]

The exact way in which PR is calculated is a google secret, but all specialists agree that the scale is algorithmic, which means that one link from a PR 5 site will boost your own PR more than 100 links from PR 2 sites.
following chapter.

Good post, but I think you mix SERP ranking and Google Pagerank (http://www-db.stanford.edu/~backrub/google.html) (section 2.1.1) that is no secret as far as I know. There are a lot of third party page rank calculators, and I have not seen any that gives a different result from Google's.


From the little information revealed by Google, we can conclude that the Pagerank calculation is indeed secret. The paper you refer to shows the basic idea, but seemingly many refinements have been made in the algorithm, see for instance Matt Cutts talking about purchased links not transferring PR.

The tools you refer to do not calculate the PR, they just retrieve it from Google (at least some of them via Googles toolbar interface) and show it. You would need information on billions of pages and links in order to actually calculate the PR, even if you knew the algorithm in detail.

all the best

- Sam

[kgun]

The tools you refer to do not calculate the PR, they just retrieve it from Google (at least some of them via Googles toolbar interface) and show it. You would need information on billions of pages and links in order to actually calculate the PR, even if you knew the algorithm in detail.

I thought of that possibility myself and waited for this answer. But do you think the "pagerank" algorithm is so much changed? May be it is improved on detecting link spam, but in the end a sort of (weighted) voting is used. How many links of pagerank x, point to your site / page?

So pagerank must not be mixed with SERP ranking was my point. I think that is much more complicated, even if there is correlation (linear relationship) between pagerank and SERP ranking.

[SemAdvance]

Mike21 Wrote
The exact way in which PR is calculated is a google secret, but all specialists agree that the scale is algorithmic, which means that one link from a PR 5 site will boost your own PR more than 100 links from PR 2 sites.following chapter.

Actually I'll take 100 PR2 on topic inbound links over one PR5 link anyday.

I also have to disagree that the scale is algorithimic. The scale is a scale...it is not an algorithim.

Algorithms were first used as a means of recording stored procedures for solving complex mathematical equations, for example finding the common divisor of two numbers or multiplying two numbers.

Another issue regarding algorithims and computers, is the time factor.

Google and other search engines use a heuristic algorithms. Their goal is not to find an optimal solution as many would be led to believe, but to find an approximate solution.

Why is this done??

Heuristic search is informed search and takes much less time than uniformed search.

When delving into PR and algorithims it is best to remember the ranking algorithim consists of over 100 parts of which PR is but one.

It is far better to make sure your pages are correct from top to bottom and double check again...than to spend countless hours trying to find the KFC Recipe or what makes Green Ignot Bar work.....

[dburdon]

I'm forming a view regarding category specific page rank. That is, pages with a tightly clustered, and on topic, link base will inherit better PR than competing pages with inbound links from more disparate sources.

Indeed the latter seem to be increasingly penalised.

[incrediblehelp]

I'm forming a view regarding category specific page rank. That is, pages with a tightly clustered, and on topic, link base will inherit better PR than competing pages with inbound links from more disparate sources.

Indeed the latter seem to be increasingly penalised.

So true for a while, it just might be showing in that crappy toolbar now.

[crush123]

If a certain website has a PR of 0, it is either new or it has been banned by google due to search engine spamming. You should never link to those sites, as this can result in your site being penalized as well (linking to a bad neighborhood).
Every site at first will have a PR 0.
if nobody links to a 0 PR site, then no website will get a higher PR.

[incrediblehelp]

Look at the relevance of the page when looking to recieve or link to out to a page, never the toolbar.

[dealunion]

The same question how can I view the PR of some site?
Through what means?
big thanx for your valuable suggestion!

[incrediblehelp]

The same question how can I view the PR of some site?

Install the Google toolbar (http://toolbar.google.com/), but it doesnt mean much and if your a newbie it will probably confuse you more than anything at first. Please read on it more here (http://www.google.com/search?hl=en&lr=&safe=off&q=site%3Awebproworld.com+google+toolbar&btnG=Search).

[braknews]

If you have a number of URLs you want to check there are third party tools to give you their PR without having to visit each one individually.

I use this one -> http://www.thinkbling.com/prcheck/

[Peter (IMC)]

* PR
* Anchor Text
* Keywords in Anchor text also in page it self

Not in that specific order, but if you don't have those 3 parts right, the link might just as well not exist.

PR Rules, but only if you get the other 2 also right.