Where to focus your optimization efforts now for optimum results.

• We all know that page titles, meta descriptions, site content, URL formats, 301 re-directs, link building, html site maps and Google site maps all contribute to improving the ranking of a site. However, has any research been undertaken about the quantifiable benefits of each action?
  
  

  For example what can we expect in terms of improvement in ranking positions for each task undertaken? If you do know of any research in this area, could you please let me know what it is?

Answer: That's a great question. The exact effect each factor has is something that's extremely difficult to test, because there are so many variables in play for each site. Those variables involve both what's happening on the site as well as who's linking to the site, who's linking to the sites linking to that site, who's linking to those sites, etc...

Since PageRank is an iterative algorithm that takes into account millions (if not billions) of sites and their linkage patterns, it's hard to track linking effects. Add the fact that different keywords and industries have different levels of competition and are often treated differently by the search engines and it gets even more complicated.

However, assuming that your site is indexable (i.e. no major crawling or duplicate content issues) then we'd say 90% of your rankings are going to come from:

1. your incoming links, and
2. your page titles.

The rest of the stuff helps too, but is small in comparison to those two. And, yes, most people are pleasantly surprised that it can be boiled down this simply.

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