Page rank (Last edited: Thursday, 8 November 2007, 07:02 PM)
Page Rank (PR) is a term coined by Google that I find is often misunderstood. When you start out a new site, Google assigns PR0 in a tool bar. PR is only a Google measurement of page importance, MSN and Yahoo use something similar called link popularity but in those models a link is a link is a link. Google says that not all links (votes) should be counted the same so it developed page rank which combines quantity and quality of in-bound links to determine the page rank of any given page. Tool bar PR measurements show as numbers between 1 and 10 which is really just an arbitrary number.
There are several things that are important to note about PR that many folks don't really get.
The scale is really logrithmic so a PR 2 is more than 2x PR1. So if you 'came out' with PR2 (I'll explain what I mean by that in a second) the next PR update won't necessarily show you at a PR4 even if you continue to work on your site at the same pace.
The tool bar is just a tool. It can only measure 10 digital increments when PR accumulates at a very minute level.
All pages that are indexed by Google actually have PR (very, very little) even when PR tool bar shows zero. A page gets into Google by having links point to it so Google can find it. A page may need to be visited by Google (or any other search engine spyder) several times before getting into the index. If a page shows up with grey in the toolbar be wary, it's probably been banned. If you want to know if a page has been indexed just type the full URL into Google's search bar (e.g., http://www.mydomain.com/) and if it's in then Google will produce a return and if it's not, it will say it can't find anything.
Update to preceding point: I'm not sure today if a page is in the Supplemental Index whether the PR0 is an absolute zero or if it is still retaining some minuscule amount of page rank. I am hoping to conduct tests to try and resolve this issue in the future but for now, we will assume that if Google is throwing a page into the Supplemental Index, it is stripping all page rank value from it.
You can manufacture your own PR just by getting more pages in Google's index.
Google has some level of PR estimation and re-estimation going on all the time (per Matt Cutts - Google employee and spokesperson "I believe that I’ve said before that PageRank is computed continuously"). When it rolled out a new infrastructure architecture about a year ago, it enabled the constant advances in PR to be reflected in the results without going through a 'dance' which used to occur first monthly then quarterly. A dance would reset all data centers at once. Would take a few days to complete.
So PR gets adjusted all the time - from Google's perspective. Toolbars do not pick up these changes and that's where folks get overly obsessed and can make unwise decisions. Also Google seems to have departed from any semblance of a pattern on toolbar updates so you can wait 4 months or more to see a change.
That's one reason why I don't like to focus too much on PR. Also, it's always been just one component of the ranking algorithm but folks put too much emphasis on it. If you want to rank well on Google, you now need to take into account factors of site age (date when Google first puts you in their index), age of links, size of site, and amount of related content on your web pages. I also believe that Google is taking into account visitor retention statistics for sites on the first page of a SERP and possibly SERP pages beyond page 1.
OK, getting Google to show any PR is always a major accomplishment only because all other web site owners treat you like crap until you do. Page rank is getting harder and harder to score. Getting to a PR 2 - 3 is pretty easy as long as you work it. Getting to a four is medium hard, getting a 5 should make you proud and getting a PR6 or higher is stellar. The reason for this, I think is because so many more pages have been added to the index over the last 2 years. Google may have adjusted downward the amount of PR a newly indexed page gets which used to be .15. Please note that I don't have a shred of proof for any of this. Also with the supplemental index and general changes in page indexing processes the number of pages a site has in the official index with contributing PR tend to be far less than it used to be. This is something those of us in the trenches observe but Google doesn't address in any forum.
I did see where a a website went from PR0 to PR5 in one cycle (about 4 months) which is pretty hard to do. I reverse engineered what he did and he 'bought' his page rank with paid links. He was pretty selective so it worked - for now. But note that Google has publically stated that they are on a mission to find and discount paid links so I've not built that into our plans. Also it's expensive. (BTW I used to be a huge paid link purchaser, now reformed).
What you need to know is that the tool bar is notoriously off at any given time. But if you are searching on a term and see the top slots are filled by PR6 and PR5 sites, and they are older sites, and they are large sites, your job is a LOT harder. If you can find a PR4 or a PR3 site in the top 5 positions in Google it's usually a good indication that doing things right may get you past the big guys.
