Google Latent Semantic Indexing Caught in Action or Something Else?

Browsing through my logs the other day I checked out a random visitor who landed on our Distinct SEO Web Review page. Nothing to shabby, however, the keyword used to hit the page was interesting. Our visitor used the term ‘SEO Website evaluation’ where we rank #11.

Google LSI 1
Why I find this interesting is because the content on this particular page– there is no instance of the term ‘website’. The only occurrence is located in the actual page name: seo-website-review.html. The entire page uses the term ‘web site’ with the space. This is either an example of Google giving page names considerably more weight in ranking than most believe or an example of LSI in action. (Currently I would opt for the latter explanation.)


Out of curiosity, I checked out where we rank for the same search phrase, only this time with a different spelling: ‘seo web site evaluation‘. Results? Page 1 ranked #8.

Google LSI 2

So how was this possible? Well I believe this is an example of Google’s Latent Semantic Indexing Engine/Algo (whatever you want to call it) in action. What is LSI? Well theoretically LSI is a complex statistical model that of analyzes relationships between a set of documents and the terms they contain by producing a set of concepts related to the documents and terms. For example, the word ‘DELL’ would return the word ‘COMPUTER’. Google obviously has the mental and physically capacity to make use of the model, however, SEO tools have begun creeping into the mix citing ‘LSI REPORTS’ among other things.

LSI SEO Tools a Scam?

I believe at the heart of LSI lies a viable model that can be used to help search. The SEO tools developed with ‘LSI’ capabilities are probably not reflective of the real model. I’ve read the original LSI document from the Ph.Ds who wrote it, and even though I have an economics degree I had a tough time understanding the entire document. Very few people can fully comprehend LSI and even fewer can capture its fundamental essence within a worthy tool. I’m not convinced any SEO tool provides REAL LSI reports.

So what’s really in these supposed LSI tools? LSI is far more than just keywords, but SEO tools are basically designed around producing keyword reports under the ‘LSI’ moniker. These tools are essentially glorified thesauri. Basically, Wordze’s ‘drill down’ tool is what other SEO tools call LSI. Until I can be shown otherwise SEO tools developed for ‘LSI’ functions are really just drill down keywords tools and fall short of reflecting the complex LSI model’. This doesn’t mean Google or other statistical savvy firms can’t and don’t use the real LSI, but chances are your understanding and tools aren’t the real deal so proceed cautiously.

[tags]google lsi, lsi, seo lsi, lsi tools, latent semantic indexing[/tags]