How to Google Calculate PageRank

PageRank on wikipedia is a link analysis algorithm, named after Larry Page, used by the Google Internet search engine that assigns a numerical weighting to each element of a hyperlinked set of documents, such as the World Wide Web, with the purpose of “measuring” its relative importance within the set. The algorithm may be applied to any collection of entities with reciprocal quotations and references. The numerical weight that it assigns to any given element E is also called the PageRank of E and denoted by PR(E).

PageRank is only one of numerous methods Google uses to determine a page’s relevance or importance.

I find several calculations from several sources, under this several calculations from google

• Google interprets a link from page A to page B as a vote, by page A, for page B. Google looks not only at the sheer volume of votes; among 100 other aspects it also analyzes the page that casts the vote. However, these aspects don’t count, when PageRank is calculated.
• PageRank is based on incoming links , but not just on the number of them – relevance and quality are important (in terms of the PageRank of sites, which link to a given site).
• PR(A) = (1-d) + d(PR(t1)/C(t1) + … + PR(tn)/C(tn)). That’s the equation that calculates a page’s PageRank .
• Not all links weight the same when it comes to PR.
• If you had a web page with a PR8 and had 1 link on it, the site linked to would get a fair amount of PR value. But, if you had 100 links on that page, each individual link would only get a fraction of the value.
• Bad incoming links don’t have impact on PageRank .
• Ranking popularity considers site age, backlink relevancy and < backlink duration. PageRank doesn’t.
• Content is not taken into account when PageRank is calculated.
• PageRank does not rank web sites as a whole, but is determined for each page individually.
• Each inbound link is important to the overall total. Except banned sites, which don’t count.
• PageRank values don’t range from 0 to 10. PageRank is a floating-point number.
• Each PageRank level is progressively harder to reach. PageRank is believed to be calculated on a logarithmic scale.
• Google calculates pages PageRanks permanently, but we see the update once every few months (Google Toolbar).

we don’t know surely, but with this calculation is seo we are better and directional