Imagine a network of a dozen websites. Each one has a number of links going in and a number of links going out. The sites vary in size and some are less or more connected than others.
Start anywhere in the network and follow a link at random. Then pick another link, and make your way through the network clicking randomly. Logic dictates that those sites with plenty of inbound links will get the more random visits than those with few, but there is a little more to it than that.
Consider what would happen if the biggest site on the network, the one with the most inbound links, had only one link heading out. It would be frequently visited, but all visitors travelling the link network would go through to the next site too. That site only has a single link leading to it, but it’s a very good one. Like all the best links, it comes from a site that is both strong in terms of its own link profile and choosy about who it links to.
The calculation of PageRank (and TrustRank, mozRank, and other associated measures) is a little like being judged by the quality and quantity of your friends. If you have lots of trustworthy friends and they, in turn, are linked to lots of good friends of their own, your reputation will be good and your rank high. If you have a friend who is known to be untrustworthy (a paid link farm, for example), you’ll be tarred with the same brush. If you have no friends at all, you will have no reputation and zero PageRank.
PageRank is not as crucial as it used to be. Google’s algorithm has evolved, but it is still the most common way of evaluating potential link partners. It’s usually given as a value from 0 to 10, the higher the better.
There are two things to keep in mind. First off, this scale is technically ‘Table PageRank‘ and not the exact value used by search engines, and second, it’s not updated very often. A site may gain 200 high-quality links in its first three months, but still appear to have 0 PageRank. It could be ranking well and delivering good value to linking partners, but the PageRank value won’t be updated any faster.
While a PR value of 3 or more shows that a site is well established and has a reasonable authority, it’s often worth looking a little more deeply at highly active sites with low PR. They could be just as valuable while they’re waiting for their rank to be updated. mozRank is very similar to PageRank in concept, but it doesn’t have the slow update problems. Also, it is being maintained by SeoMoz and not Google themselves.
Many SEO professionals are moving away from PR and towards mozRank as a measure of link profile quality. Both can be displayed on free toolbars, so it’s usually worth taking a look at both before forming an opinion about how well linked a site is.
0 comments:
Post a Comment