Is there any evidence that PR is tied to a scale of backlinks

[cgallent]

Any thoughts to a "scale" as it related to PR?

PR0: backlinks = 0/banned/unindexed
PR1: backlinks > 0 & <= 5
PR2: backlinks > 5 & <= 10
PR3: backlinks > 10 & <= 15
PR4: backlinks > 15 & <= 25
PR5: backlinks > 25 & <= 100
PR6: backlinks > 100& <= 500
PR7: backlinks > 500 & <= 1000
PR8: backlinks > 1000 & <= 10000
PR9: backlinks > 10000 & <= 100000
PR10:?

Any logic to this or an amended scale? I'm also sure that the quality of the backlink plays into this as well. Just looking for approximations.

[ciml]

The scale is believed to be logarithmic. The early Google papers mention that the scale was logarithmic back then, and every quantitative analysis (reverse engineering) I'm aware of comes to that conclusion.

In a log scale, PR5/PR4 = PR4/PR3 = PR3/PR2 etc., a very useful feature (notable Pareto/Zipf Web analogies have been made by Nielsen and others).

People disagree over the 'log base' (assuming a coefficient of 1); in other words "A PR6 is as good as how many PR5s?"

[crxchaos]

I have two web sites, one has four backlinks and the other has three. They have a page rank of 4 and 5 respectively.

How does that fit into the scale?

[Cianna]

Nothing is quantifiable about Google these days, IMHO. I have 37 backlinks according to AlltheWeb, including a PR6 and two PR4s, many of my pages are indexed, I'm not banned, and all of my pages show PR0. It's not pretty.

[Wired Suzanne]

PR(a)=(1-d)+d*SUM((PR(I->A)/C(I))

The PR of a page is determined by the PR of every page I that has a link a link to page A. For every page I that points to page A, the PR of page I is devided by the number of links from page I.

[ThatAdamGuy]

Cianna,

I don't see your site in your profile, so I can't check for you, but do be aware of the generally-consistent screwiness of the toolbar's showing of PR.

All but one of my pages show "Current page is not ranked by Google" (PR0), but at least as of a week ago, several kind WW'ers informed me that my pages mostly showed up ranked as a PR5 on their toolbar.

So your PR0 may, in fact, not really be PR0.

[Cianna]

ThatAdamGuy:
Thanks. It *is* the homepage listed in my profile. Is it not showing up? I know all the rational explanations, but it's still frustrating. *rueful grin*