Has google changed something recently?

Hello everyone,
I hope you are very fine...

Well... I was wondernig why nobody else have noticed this. Maybe it is usual?

It looks like Google, in its most recent PR calculation, have lowered the PR of several sites...

For example,
mail.yahoo.com has dropped from PR9 to PR8 (it is hard to assume they have lost some backlinks or something)
www.php.net has dropped from PR10 to PR9
well.. the internal pages in my site have dropped from PR5 to PR4 (the index page remained at 5, though!)
A friend's site got all his pages dropping from PR5 to PR4.

Is this usual? Did google change its algorithms? Or maybe the site with the highest PR in the world, got some more links, so Google had to normalize?

What do you think?

Yours,
msaad

I think the PR algo was adjusted. I went from PR6 to PR5 with an increase of 70-80% in BL's during the last update. SERPs positioning did not change even one position. That leads me to believe that it was an across the board adjustment to the PR levels.

Yes I think they did adjust PR. Same thing as you got here.
More links but less PR. They seem to be doing this once in a while.

When did you notice this, did it change in the last couple days or during one of the normal PR updates?

Thanks,

My two sites dropped from 5's to 4's even though backlinks increased. Glad to hear it may have been acroos the board

The original PR algorithm was quoted as being:

PR(A) = (1-d) + d (PR(T1)/C(T1) + ... + PR(Tn)/C(Tn))

where d is a damping factor that was originally set to 0.85 (values range from 0 to 1).

I too have seen several sites that I monitor drop in PR. It looks to me as though Google are tweaking the damping factor - that's what it's there for afterall :-)

Regards, S

Well, actually i noticed it about 10 days ago, but i am not an SEO expert. I am not sure whether this was the normal PR update, or something extra!

Seems the problem is universal!! Does this PR decrease have any implications? Or should it just be ignored?

Thanks a lot,
msaad

If you see PR5 drop to PR4. It's likely that PR5 is a weak PR5. The SERP change (if any) is not as dramatica as it seen on toolbar

just because you're seeing PR changes across some sites doesn't mean that google tweaked the algo. it could be a bit of a chain reaction, especially if you're noticing changes within a specific "genre" of sites.

if they're all interlinked to some extent (ie site A links to B which links to C which links back to A), if one of the sites that "feeds" this whole cycle drops, a lot of sites could experience a drop.

yes google updates it's database 1-2 days back