tedster - 6:34 pm on Sep 29, 2008 (gmt 0)

How about pages found to be selling links and losing the ability to pass PR? Wouldn't that be related to a negative trust factor being applied to the sites selling links, at least for the links in question.

I'd say yes. Notice that the quote that I put in the first post taslks about monitoring ads on the page to determine trust?

But the point is, does that affect nullifying the benefit of just those links in particular, or all the links on the pages selling them, including internal links and editorial links not being paid for?

One of the things Google did to whack paid links was to hit the PageRank. We also know that back in January, Google changed "something" about the PageRank formula. Do you think PR now includes a trust component?

what about servers, or hosts?

I've got a strong feeling that servers and hosts can be wrapped into the formula for trust, but on a case by case basis - and this may also have a manual review component if a host is flagged by the algo as looking dicey. The Yahoo paper on Link Spam Detection that I mentioned above talks about nodes, where ""nodes may be pages, hosts, or sites..." Of course, that might mean "hostnames" as in subdomains - and there is no technical definition for "page" which is a very fuzzy concept.

Has anyone ever defined such a list of [seed] documents?

I can only wish. Many people assume that DMOZ is one, and .gov domains are another. The quote from the patent mentions Amazon, so that would be a third, and I'd guess that most of the .int domains are a fourth area for trust seeds. I'm sure the list is a lot bigger than the few I just ticked off.

I can't imagine how we might reverse engineer that list, since Google's trust metrics are not published anywhere, and are not likely to be. So we can only guess, and since even major newspapers have been caught up in the link-selling witch hunt, some of my previous assumptions about trusted sites are pretty much out the window.