Its because Google update its index frequently and highlight fresh content.
Whereas Yahoo! indexing is little slow which is why websites hold rankings for long period.
i agree with KATEBLAKE
It is obvious as Google has many site which are fighting for good page rank,that's why Google has to be very strict about ranking.
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Yes I'm agree with ... google frequently changing his algo and indexing faster so there position are not be stable. how ever yahoo bit also after all google is the best
There are many sites who want to be a first position in Google and Google change the index frequently and it is strict in page rank and Yahoo have stable page rank.
sorry but i am bit disagree as i seen many updown in my ranking sometimes its on 4th position sometimes its no where in top 100 not for 1 keyword but so many keywords
I have seen many sites which want to get first position in Google and Google changes the index very frequently and it is very strict in ranking the pages. Yahoo has stable PR.
Because on Yahoo competition is not that big in certain niches.
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To me Google is more user friendly. though both use olmost similar alogorithm(webrank for yahoo and pagerank for Google).
If you can use latest SEO techniques you can easily improve the PR of your website.
Google often changing the algorithm & indexing faster so there position is not be stable. How ever yahoo bit also after all Google is the best. You must know all about this.
There are many sites that are keen to get the first position in Google but the processes of indexation changes quite frequently due to which the PR also changes.
Several sites want to achieve the top point in google page ranking. But google changes its indexation process very frequently. This changes the ranking of different pages subsequently.