Thank you, Aaron. That's for taking the research paper (PDF file) about detecting link spam that Gary wrote about earlier and breaking it down in non technical language (and Jim Boykin summarizes Aaron further here). Aaron finds things like the paper says having .edu and .gov links are a good thing, don't worry about having a few spammy links and the more trusted links you have, the better.
I was thinking last night about the way to describe some of the changes or generational evolution we've seeing with counting links, and I thought it might be helpful to break it down this way:
Counting Links / Referendum: Before Google, other search engines made use of links to determine which sites might be important. But this was mainly a counting exercise. The more links the better, regardless of the quality of those links.
- In simple terms, each link counted the same.
- In election terms, it was like a referendum. Every voter had an equal say.
Weighted Links / Electing A Congress: Google's PageRank system helped usher in a change to weighting links, that not all are as important as others. The system worked to figure out what were the most important links and give sites getting those links more credit -- the authority pages, to use a popular term for this.
- In simple terms, not all links are credited equal. Some links are worth
more than others.
- In election terms, it was as if Google looked at all the links across the web, determined who seemed to get the most, then let those authorities serve in a "congress" of sort in making the big decisions about what's good on the web through the link votes they cast.
Trusted Links / Qualifying Representatives
This is what we've been moving to. When PageRank knew a link was "important," that wasn't the same as trustworthy despite the authority misnomer. It only meant knowing that some particular link should count for more because the page the link was on had a lot of people "voting" for it. You can scam that type of voting.
- In simple terms, some links are worth more than others after using some
checks-and-balances to eliminate the scamming.
- In election terms, it's as if after a congress is elected, you go back and check the campaign contributions. If you find something iffy, then some particular congressperson's vote might not count for as much as others. Or perhaps you watch their voting record, to see if they know what they're talking about. Being popular as everyone knows doesn't necessarily mean you're an authority!
That's a rough idea, and I'm playing at refining it more, but I thought I'd share it now. Remember, it's also not just about how much a link counts for but the text that's in and surrounding the link, along with a lot of other factors. Also see Yahoo My Web: An eBay For Knowledge on how search engines hope to tap into trust in ways beyond link analysis to improve results.