The following is taken from http://infolab.stanford.edu/~backrub/google.html and the actual equation may have been changed since, but I thought it would be fun to share here at DigitalPoint. If you find it helpful, I could use some +Rep 2.1.1 Description of PageRank Calculation Academic citation literature has been applied to the web, largely by counting citations or backlinks to a given page. This gives some approximation of a page's importance or quality. PageRank extends this idea by not counting links from all pages equally, and by normalizing by the number of links on a page. PageRank is defined as follows: We assume page A has pages T1...Tn which point to it (i.e., are citations). The parameter d is a damping factor which can be set between 0 and 1. We usually set d to 0.85. There are more details about d in the next section. Also C(A) is defined as the number of links going out of page A. The PageRank of a page A is given as follows: PR(A) = (1-d) + d (PR(T1)/C(T1) + ... + PR(Tn)/C(Tn)) Note that the PageRanks form a probability distribution over web pages, so the sum of all web pages' PageRanks will be one. PageRank or PR(A) can be calculated using a simple iterative algorithm, and corresponds to the principal eigenvector of the normalized link matrix of the web. Also, a PageRank for 26 million web pages can be computed in a few hours on a medium size workstation. There are many other details which are beyond the scope of this paper. Group theory hard at work
Yes, it has been discussed before, a couple of times: http://forums.digitalpoint.com/showthread.php?p=2087469 http://forums.digitalpoint.com/showthread.php?p=2390495 http://forums.digitalpoint.com/showthread.php?p=1076537 http://forums.digitalpoint.com/showthread.php?p=690518 http://forums.digitalpoint.com/showthread.php?p=575123 -Michael
Nice job exponent, But this is only one PR calculation formula, In public Google never disclosed its PR calculation formula, only Matt Cutt speak on a public conference that google update the PR of websites in every 3 months thats all.
No, it's the original PR formula that was patented PR values update every three months give or take, the PR forumula doesn't change.
not really that useful or anything that hasn't been seen before over the years ... imho cutting and pasting information purely to gain rep points is pretty lame.