Michael G. Schneider wrote:
> Suppose a PR-update has been done on Jan 1st and the next one will be done
> on Mar 1st. When will the PR be calculated? What information will flow
> into this calculation? Will all activities between Jan 1st and Mar 1st
> influence the PR? Or will the PR reflect a snapshot taken (for example) in
> the last week of february?
> Michael G. Schneider
Judging by the way Google Image apparently works (where indices are updated
in long cycles), here is what I think. It appears as if Googlebots pick up
images on a daily basis (judging by my logs), accumulate them and then,
later on, run some computation to rank them appropriately. Perhaps this way
they can tell if an image URL was temporary (i.e. bound to be broken) and
likewise if a normal URL is spam which got removed soon after appearance.