LSI and Link Popularity

When Paypal's official Web site no longer ranked #1 in Google on asearch for "paypal," it was obvious that Google had become more aggressivein penalizing sites with "unnatural" backlink anchor text. Although thehigh-profile Paypal example has since been rectified, thousands ofwebmasters are suffering the consequences of not ranking for even theirofficial company name, let alone their top keywords. It is important forsearch engine optimizers to understand both how anchor text penaltiesare being applied and how LSI ensures that anchor text variance will notdilute a link popularity building campaign.

Anchor Text Penalties

In the past year, webmasters have found that the aggressive linkpopularity building tactics that work well in search engines such as Yahoo!do not fare well in Google. Google has implemented several features tofilter out sites that appear to have an unnatural backlink structure;one of these features seems to be specifically penalizing sites withunnatural backlink anchor text.

It has always been an SEO best practice to use descriptive anchor textin both external and internal links. But search engine optimizers haveoften focused on a single keyword phrase when choosing anchor text,especially if their topic has one keyword that receives vastly moretraffic than any secondary keywords. Since good links are hard to come by,they do not want to "waste" any of those backlinks with anchor text thatdoes not contain their main keyword.

The drawback to this approach is that it can be interpreted asunnatural by a search engine. A site with organic, passively-obtained backlinkswill have a wide variety of backlink anchor text variations such as:"official site title," "keyword," "keyword synonym," "www.thesite.com"and even "click here." If the vast majority of a site's backlink anchortext is simply "keyword," it is obvious to an algorithm that the linkpopularity was not obtained organically.

Latent Semantic Indexing (LSI) Basics

Let's now touch upon the myth I mentioned before, that if a backlink'sanchor text does not contain your Web site's main keyword, its power iswasted. The concept of latent semantic indexing, which may be morefully implemented by major search engines in the near future, will provethis myth to be false.

Latent semantic indexing can help overcome the "vocabulary mismatch"problem when a human uses a search engine. Individual words do not alwaysprovide reliable evidence about the conceptual meaning of a document.For instance, a Web page that is highly relevant to the term "laptop"may never use the term "notebook," however it is clear to a human beingthat "notebook" is often used as a synonym for "laptop."

While it is beyond the scope of this article to discuss the mathematicsbehind LSI, its implications for search algorithms are simple. LSI canuse statistical techniques to create a semantic analysis for any givenquery topic. In practice, this means that a page can be consideredrelevant for a particular keyword, even if it does not contain thatkeyword. For instance, a page that is considered relevant for "laptop" canalso be considered relevant for "notebook" even if it does not contain theword "notebook," if LSI determines that "notebook" is semanticallyrelated to "laptop."

The principle can be applied to backlinks as well. Backlinks withanchor text that do not contain your Web site's main keyword, but insteadcontain a synonym or related word, may still be giving your site a bonusfor the main keyword.

Link Popularity Building Best Practice: Vary Your Anchor Text

The recent increase in penalties given to sites with unnatural backlinkanchor text, along with the possible implementation of LSI, should givewebmasters motivation to vary their backlink anchor text heavily.Rather than seeking to only obtain links using their main keyword,webmasters should include synonyms, variations and related words. Certainly nosingle keyword variation should be used the majority of the time;rather, the text of all links should vary widely, just as they would if thelinks were obtained passively. This will ensure a site's improvement inthe SERPs, without drawing a penalty flag.

Andy Hagans is a search engine optimization consultant who specializesin link popularity building and risk management. Visithttp://www.andyhagans.com for more information. Seehttp://www.andyhagans.com/link-building.php for more information on Mr.Hagans' link building services.