A Little Piece of the Google Algorithm

GoogScore = (KW Usage Score * 0.3) + (Domain Strength * 0.25) + (Inbound Link Score * 0.25) + (User Data * 0.1) + (Content Quality Score * 0.1) + (Manual Boosts) - (Automated & Manual Penalties)

KW Usage Factors:

KW in title tag
KW in header tags
KW in document text
KW in internal links pointing to the page
KW in domain and/or URL
Domain Strength

Registration history
Domain age
Strength of links pointing to the domain
Topical neighborhood of domain based on inlinks & outlinks
Historical use & links pattern to domain
Inbound Link Score

Age of links
Quality of domains sending links
Quality of pages sending links
Anchor text of links
Link quantity/weight metric (Pagerank or a variation)
Subject matter of linking pages/sites
User Data

Historical CTR to page in SERPs
Time users spend on page
Search requests for URL/domain
Historical visits/use of URL/domain by users GG can monitor (toolbar, wifi, analytics, etc.)
Content Quality Score

Potentially given by hand for popular queries/pages
Provided by Google raters (remember Henk?)
Machine-algos for rating text quality/readability/etc

http://www.seomoz.org/blogdetail.php?ID=1467

ps
а что .. более-менее правдоподобно

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