SERPs not only depend on BL info and/or PR, but also on the more 'conventional' things such as the actual content, keyword density, title tags' text etc. And, all this stuff varies all the time ..... even if it doesn't vary on your site, there are people out there (possibly your competitors) who are changing their site's structure and content all the time and as soon as Google caches the new content on your site as well as theirs, it affects the site's SERPs. One of the keywords I was targeting for one of my sites' pages was not very competitive (only a few thousand pages in the search result) and I was able to climb from around #20 to #4 at the moment, simply by changing the title tags, content etc. This was done in 4-5 steps and each time the new changes were cached by Google, I got closer to the top. I DO understand that PR and BLs do count quite a bit towards the final ranking, which is why I am stuck at #4 and can't go any higher until I get more quality BLs.
While I agree that the public backlinks are updated every month, I have yet to see anything which proves that internally Google is not updating links continuously, Perhaps you have some evidence of this that you could share? What makes you think that the public backlinks data base (of which Google only shows a small portion to us), is in fact the database Google uses for rankings? Nonsense. Google does not tweak its algo several times a month. New sites are shown in the index shorthly after they are spidered and do not have to wait for a backlinks update.
Thanks for that Mel! I couldn't have put it any better myself. Google constantly spiders sites and now sites as well as new pages are indexed as soon as they are spidered. And, IMO there has got to be multiple copies of "The Index" ..... One that SERPs are calculated on, another one that's used while calculating BLs etc. This is purely based on the fact that when PR is being calculated, the database would be going through hundreds (or thousands) of queries, and that would considerably slow down other operations on that database, including searches. So, there has got to be multiple copies of the index and in any case, there is no evidence to prove that the BL info or PR info that we are shown is the same that is being used to calculate SERPs. There is also some speculation that PR is being updated regularly ..... I don't really agree with that either and I believe that PR is only updated after a few days or weeks .... I am not talking about the toolbar PR, but the actual PR that affects SERPs. And Bob, those "sudden SERP jumps" that you notice could very well be due to a PR update (after a BL update). BL info on it's own can not affect SERPs, as it is meaningless until converted to something more meaningful .... Like PR perhaps??
As originally concieved Google had at least than the following databases (or indexes if you will but that is not very precise): "Main Index" Repository - compressed copies of all the full content of all web pages pages indexed Forward word barrels - thousands of barrels which comprise the forward index. Reverse Word barrels - thousands of barrels which comprise the reverse index. The lexicon - a listing of all the words and what word barrels they are in. Anchors - data about all the links they have recorded The Document index - keeps data on all pages indexed. Links - info on the origin and source of all links PageRank - info on the PR of all the pages that PR has been computed for. In addition google has a set of reverse barrels which only contain words from the anchors and page titles, and which it searches preferntially. And recently Google has added a supplemental index, which I assume is structured much like the main index outlined above. From the above it may be a little clearer that Google has many different ways of storing and using information all operating more or less in unison. I would also imagine (nothing except intuition and common sense behind it) that Google has backup copies of all of the above and could very easily also use additional temporary databases in addition to these, for instance a public and a private copy of PR and backlinks which would make it easy to update these before making them public via the toolbar and link: searches.
Someone help me out here... what is the URL of the web site which tracks the rise and fall of several hundred popular SERPS to measure overall fluctuation in the Google index? <blush>
Mel: I would agree that new pages brought into the index account more for the though the month fluctuation than tweaking of the algo. What leads you to think that Google doesn't tweak the algo? dfsweb: I would agree that PR has some thing to do with the fluctuation after a BL and real PR update. I disagree, BL updates on their own would change Rankings as the number of backlinks a page has affects its ranking.
...umm...don't know...<blush>²... There is one thing which worries me in using the KW Tracker: I'm observing a CONSTANT discrepancy for (and only for) my two most competitive KWs. It's in the order of a factor of 2..3 of the ranking shown in the KW Tracker. Today for example, one of the KWs shows at #11 in the KW Tracker, while in reality it is at #27. And it is like this since months; real ranking varies approx. in proportion with the KW Tracker reading, but is always different. How can this happen? In contrast ot that, less competitive KWs or any compounds are represented almost without noticeable difference.
How can this happen? It happens because your SERPS differ on the various Google servers. You're #3 on one Google server and you're #6 on another. On a third Google server, you're #5. The Google API used by the DigitalPoint Keyword Tracker queries one Google server and your manual searches query one or more different servers. A good way to see this in action is to do keyword lookups across many Google servers at once via the Google Datacenter Watch Tool.
What I said Bob was that Google does not tweak the algo several times a month. By algo I mean the process by which pages are ranked for a particular search term after selection from the word barrels. This is a core function of Google, and is IMO not something which is continually modified on an almost daily basis. When you see frequent serp fluctuations they are IMO most likely due to : Pages being added or dropped from the index, which is an almost continual process. New anchor text links being included/dropped from the index which again is an almost continual process. Another variable can be if there are enough pages in the short word barrels those will be ranked, but if there are not enough then pages from the long barrels will be added. During certain times of the month when Google is updating the datacenters, you may see variations in the SERPs due to accessing different data centers whose data in not yet synchronized.
Ya I agree, not on an almost daily basis. I am trying to find the link where it seems that GG indicated that is was tweaked a couple times a month. I could be wrong on that one though. But on an almost daily basis, I don't agree with that.
Maybe. Unfortunately, the McDar-tool does not permit lookups restricted to G!.at. I have a rather small site ranking well in my country, but being completely lost in a global search. The funny thing is the constant discrepancy for only very few KWs over a long time interval; there is none for all others nor for KW compounds.
Hy! Here it's Allroogle: a tool to monitoring real pagerank of all your backlink, related web site and Google mentions! all detail: www.cavone.com/allroogle
I read a post from GoogleGuy that, IIRC, PR was continuously updated, but only given to the public at certain period of time. (same with backlinks) This makes more sense, because the toolbar can say you are PR2, but you get lots of backlinks, google is crawling you heavily, and you rise in the results... yet it still says PR2. Otherwise you'd just rise in results once a month, if I understand the original post correctly.