esaslo - 7:26 pm on Mar 28, 2003 (gmt 0)

Item 1:

A link from a PR site which is low enough can REDUCE the over pagerank of the site it links to
Can you explain how this can happen? I have never heard this.

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This is simply a matter of the differential equation (math-guy, here); let me demonstrate:

Take the most simplified form of the pagerank equation:

PR(A)=(1-d) * d(...) extend to PR(A)=PR(A) + (1-d) + d(...)

OR

SIMPLY:

PR(A) = (1-d) * (P(A)/(P(B)))... + ... (P(An)/(P(Bn)))

Where the d is the modifying factor.

So, let us say that P(A) is the page's pagerank and P(B) is the number of outgoing links for any given page P.

If page P has a pagerank of 2 and has 50 outgoing links that's (2/50) * d. D is less than one (nominally set at .85); so, do a series on your own: compare the following:

P(A)= (1-.85) * (2/30) + (2/40) + (2/50) ... + p(An)
P(B)= (1-.85) * (8/2) + (7/2) + (6/4) ... + p(Bn)

Now, this is just for instructional purposes; this is the basic representation. Although the google equation might not be exact, this representation is good enough.

You can clearly see how P(B) >> P(A).

If you want to prove it, expand it with the taylor series about (1-d)*P(An)

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Item 2:

This comes from three basic facts, the most prevalent of which is my experience logging every single time I'm indexed, the dates and times, on each site.

However, adding pages consistantly is a good force against the overall number of pages on the web. I.e., overall pagerank is based on the total number of pages on the web. Increasing your internal pagecount helps to offset the increase in overall pagecount.

Its really not a "freshness paradigm" as much as it is an ACTIVITY paradigm.