Page Rank Meditations on a Theme by Matt Cutts
My Favorite Matt Cutts Quotes: (from Matt Cutts on PageRank)
Q: New Jersey SEO asked: “Will this PR update affect SERPs? Are we going to have also a SERP data refresh / update?”
A: Great question. By the time you see newer PageRanks in the toolbar, those values have already been incorporated in how we score/rank our search results. So while you may be happy to see that the Google Toolbar shows a little more PageRank for a given page, it’s not as if that causes a change in search results at that point. So you won’t see any search engine result page (SERP) changes as a result of this PageRank export–those changes have been gradually baking in since the last PageRank export.
Q: I’ll do a follow-up. Supplemental Challenged said: “The fact that Google can only create a PR update that is a full quarter behind the times is awfully troubling.”
A: I believe that I’ve said before that PageRank is computed continuously; there are machines that take inputs to the PageRank algorithm at Google and compute the resulting PageRanks. So at any given time, a url in Google’s system has up-to-date PageRank as a result of running the computation with the inputs to the algorithm. From time-to-time, that internal PageRank value is exported so that it’s visible to Google Toolbar users (see the question below for more details on the timing).
Of course, we all know that pages with higher page rank tend to be higher in the Search Engine Results Pages (SERPs). And we've all noticed that our pages have at times performed better than other times. And we've thought that it's probably in part because of page rank. And we were right.
We've noticed that sometimes our pages' SERP position can go up or down at the drop of the hat, if we get new links or we position a new item at the top of our home-page.
The comments by Matt Cutts help us to remember that the algorithms are always running constantly - suppose that, for instance, there are 1000 googlebots that are semi-randomly stumbling around the internet. They go to pages that have links, and everywhere they go, they send a signal to the PageRankCenter "I visited the page". And the rank of that page goes up. But the influence of that visit decreases with time. Maybe, of course, another googlebot will visit the page the next day, and then there will be two votes from a certain page to another page. The old vote will already count less, but the new vote will now have a large freshness value.
We've all seen our websites get ranked high in SERPs when googlebots initially find them and spend time there. But if the links to those pages disappear, then the googlebots don't visit, and the influence gradually wains. This is one of the big reasons white hat SEO is important: high-quality links are links where the bots spend a lot of time, and they are links that aren't relegated or deleted after just a few minutes/hours/weeks.
For more cute tips from Matt Cutts, check out another SEO blog with 21 Tips from Matt Cuts.