Marketing Defined

Themes and Latent Semantic Indexing - LSI for short - are paving the way that Search Engines rank your web pages, and the way they display certain sites within those rankings.

The infamous new Google LSI patent brings about the need to look at effective use of LSI to create quality web content in 2007 and coming years. …

What does the new LSI patent really mean to a webmaster?

Google’s new algorithm will scan content on a webpage and then analyze the phrases within to determine what other related [latent related] phrases should naturally occur in that document.

You can read the entire document at Google’s new LSI Patent application.

But to save you time, here is an excerpt from the patent that epitomizes the key requirements:

“The system is further adapted to identify phrases that are
related to each other, based on a phrase’s ability to predict
the presence of other phrases in a document. More specifically,
a prediction measure is used that relates the actual co-occurrence
rate of two phrases to an expected co-occurrence rate
of the two phrases. Information gain, as the ratio of actual
co-occurrence rate to expected co-occurrence rate, is one such
prediction measure. Two phrases are related where the prediction
measure exceeds a predetermined threshold. In that case, the
second phrase has significant information gain with respect to
the first phrase. Semantically, related phrases will be those
that are commonly used to discuss or describe a given topic or
concept, such as “President of the United States” and “White
House.” For a given phrase, the related phrases can be ordered
according to their relevance or significance based on their
respective prediction measures.

Simply adding keywords at random to your article and websites will no longer get you top rankings. In fact, the above excerpt plainly shows that over-optimization and duplicate content within your webpages will be the kiss of death.

What is Latent Semantic Indexing or LSI

Let me try to explain LSI in its simplest form. Say your website contains the parent theme of “golf”. If most of the authority “golf” websites on the internet contain the keyword phrase “Tiger Woods” but your site does not, the LSI based search engines will NOW know about it. They may consider you less relevant because your web page is not talking about “latent” topics related to your parent theme…. which in this case is “golf”

How Will LSI Change Creation of Web Content

We know that in 2005 and 2006 keyword density figured prominently when writing new articles. The recommendation was a density of between 2% - 6%, but that was before the new LSI algorithm.

From 2007 onwards, it becomes crucial to use theme density instead of over-optimizing with keyword density!!

The patent very clearly indicates the huge role LSI will play when Google evaluates the relevance of a page… ranking it accordingly by closely looking at semantically related phrases and co-occurrence rates.

Thankfully, simply adding a keyword hundreds of times to an article no longer works. Google has finally caught up with the garbage scraped, duplicate content that shortsighted webmasters seeking instant gratification or “adsense riches” have crammed the w.w.w. with.

The effect of hundreds of incoming links is also now lessened. Incoming links still do matter, but not just any links.

Instead of concentrating on linking only to the home page, deep linking to many pages in a website, using anchor text that relates to the “theme” of the page you choose to link to has now become crucial.

The “anchor text” keyword must also be altered “thematically” for inbound links to any one webpage. Let me explain.

For example if the page you are linking to is about “dog kennels”. Google would first expect the domain name to naturally occur in anchor text [ie. www.dogkennels.com]. Then - some variations of related key phrases used in the anchor text of such links should be:

“dog kennels”
“dog boarding”
“dog holiday kennels”
“dog minding”
“dog houses”
“dog beds”

You would have heard some of the newest buzz words on popular webmaster forums surrounding the Google LSI patent are “silos”, “themed websites” and “expert verbiage”. But in reality professional SEMs have been using these very same strategies for years on end for consistent, high SE rankings for their clients. The proper application of silos and themed websites had been a closely guarded secret of these professional SEO firms… up until the advent of Latent Semantic Indexing.

Please comment if you would like to add your thoughts on LSI, the Google LSI patent and themed websites - it’s always great to learn from our readers.