Hi according to my last research the more pages you have in your website the more PR you can achieve if you use a hierachical structure in your site. This is because each one page have a minimun PR of 0,15.

If you have 13000 registered users in your forum you have 13.000 pages to be indexed. I know they are useless pages, but all of them have 0,15 PR power.

according to my research if you link back all those pages to the forum home page, you will increase the forum PR by 13.000 * 0,85 (0,15/30) = 55,25 im estimating that each profile have 30 outgoing links.

This is a very high number my friends.

Due to the logaritmic scale of the google page rank algorithm this 55 points can push your page from PR 2 to PR 3.

So why to block member profiles pages for being indexed??, besides they are content useless the contribute to our interal Page rank.

I though we where done with PageRank calculation attemps

You cannot accurately calculate the PageRank, since you do not know how Google computes it. Of course, we know the main principles, but nothing allowing us to write down a formula.

Anyway, my opinion is that SE, and especially Google, have huge statistic capabilities, and that they do use them. Among the stats that could matter is the relevancy of each page.
So yes, on the one hand, the more page, the more PageRank, but, on the other one, the better relevancy, the best SERPs.

And our goal is SE referrals, not really PageRank.

It's of course up to you to use or not use the disallow on member profiles on your forum, but our strategy here is to put the more weight on the good pages, eg topic and forum pages. Adding member profiles would decrease the overall relevancy of the forum IMHO. It's off course hard to tell how and when could this make any difference, but ... that's the kind of strategical choices to make while search engine optimizing a web site. Some forum could need their members profile to be indexed after all.

phpBB3 does not allow guest to view profiles by default for example.

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sorry for talking again about PR calculation, but those days PR is a major factor in ranking pages. Some other engines uses google PR to rank pages. And riectories also do it.

Besides we find quality pages to be indexed, PR have not to be leaved alone.

I find this seos world really interesting and complex. And after researching a lot i could find some free seo courses at the net really valuables. I recomend the WEb CEO university free course. I learn a lot using this resourse and onle read 12 chapters, and there is other 20+ more chapters do read.

Using the mods here in phpbb-seo.com i really could improove my site traffic. Becasue of that i always come back to participate, ask and collaborate with others.

Thank you for your answer

I was just stating that we cannot really calculate PageRank, at least the one used by Google, just because we do not have access to the real formula nor to the data involved.

Then, of course, we can tell if something is likely to help out or not, but the answer will always be relative to many factor (type of content, surrounding of the web site, competitors strength, web design, SEO technique implemented etc etc ...), thus never absolute (like ten pages will give 0.352 PR back).

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