Single backlink vs Multiple backlinks on the same page

Question

Having one backlink of a website on other's website's page.

vs

Having more than one backlink of the same url on other's website's page (same page).

Will the effect be same on PR?

Answer 1

It doesn't matter...

Since by formula it sum links like this:

PRa = ( 1 - d ) + d(PRb/Lb + PRc/Lc)

PRa - PageRank of page A
PRb - PageRank of page B, Lb - Links on page B
PRc - PageRank of page C, Lb - Links on page C

So if you have one backlink from page B it will be like:

PRa = ( 1 - d ) + d(PRb/1 + PRc/Lc)

And if you have two backlinks from page B it will be:

PRa = ( 1 - d ) + d(PRb/2 + PRb/2 + PRc/Lc)
PRa = ( 1 - d ) + d( 2(PRb/2) + PRc/Lc)
PRa = ( 1 - d ) + d( 1(PRb/1) + PRc/Lc)
PRa = ( 1 - d ) + d( PRb/1 + PRc/Lc )

So it doesn't matter at all... one or million it gives you the same PR value from it...

Answer 2

Hard to say. According to the PageRank formula more PR should be sent to the page receiving the backlinks. But it is possible that Google has implemented spam controls to limit abuse of PR.

Obligatory PR statement: don't worry about PR. It's worth a lot less then you think. It used to be more important but since its original implementation it has been greatly devalued in Google's algorithm.