Originally Posted by acdra Looks like most of us have moved far away from answering the original question about whether there is any value in linking to PR0. So here's the PR equation when it was first released: PR(A) = (1-d) + d(PR(t1)/C(t1) + ... + PR(tn)/C(tn)) It is generally believed that d=0.85 So what the equation tells us is PR = 1 - 0.85 + (contribution from backlinks) = 0.15 + (contribution from backlinks) A PR0 page would then have at least 0.15 to give to pages that it links to. So it's still worthwhile to get a link from a PR0. The contribution to your pagerank may be small, but it is positive.

Haha,This equation is good.But there are some changes.I mean google have google dance once a week.I can't deny that backlink is one of the factor on increasing PR,but there are still other factor like sites CTR,how many ppl bookmark your sites and how sticky there are your sites(how long the visitor stay in your sites per visit)
These is information from the google announcement on their page rank US patent in 2005.While
maybe now is changing cause google have their dance quite frequent.Google don't like anyone know their page rank algorithms(To prevent spam).There are someone say that
the amount of discussion about your sites in other sites is one of the factor,but I not sure about that.If I have not mistaken,the equation is not announced by google but stanford*(at very early year the goolge have made,cause the founder are studying in standford),so it cannot represent google.Anyway,you still can use the equation but don't to concern about it accuracy.