Latent Semantic Indexing -- The Basic Understanding

Talk of Latent Semantic Indexing or LSI has been cropping up a lot in the last several weeks. I don’t know about you but those who write about it, hasn’t really helped me much in learning the concept Google is now emphasizing in their algorithm mix. Thus, I did some research and I believe I have a better handle of LSI. So here is my attempt at explaining LSI – with my article “Understanding Latent Semantic Indexing”

Now, I didn’t include everything, -- I didn’t want to bore you with how LSI prunes, and cuts the ambiquous words out of the mix before applying their mathematic matrix and thus, ranking to words and phases. But instead, I just gave you a flavor of what it is and how you can maybe adjust to the changes.

Even though LSI is a mathematical solution, if all is as it claims, it will give better search results. One thing to note, with the mathematical matrix used in ranking keywords – it will be a little more difficult to know what keywords or keyword phases will rank high or not, which I might add, may be Google’s purpose (wanting quality to prevail, while eliminating or at least diminishing the SEO blackhat tactics).



Understanding Latent Semantic Indexing
By Vickie J. Scanlon


There has been much talk lately of Latent Semantic Indexing – do in part to Google placing a higher relevancy to it in it’s algorithms, and consequently the hits and lower page rankings some webmasters encountered when Google instituted the change. If you are utilizing SEO or wanting to-- learning about LSI is important. What is Latent Semantic Indexing and how can it help or hurt your site? These are the questions that I will attempt to address in my article.


What is Latent Semantic Indexing?

Latent Semantic Indexing has been around for a while. According to the Wikipedia Encyclopedia, LSI was first patented in 1988. The LSI concept attempts to convert information from computer databases into normal-sounding human language. Understand? Yeah, my thought exacting. Let me compare and contrast and maybe, as for me, the understanding will be a little clearer.

With the old system of keyword search, the search engine would go through your web page and grab the keyword or keyword phases that were relevant – if no relevant keywords were present – the information on the page would be tossed aside and not be considered relevant—no in-betweens, and thus, the search engine algorithm would rank the page accordingly.

With LSI, an important step was added to the search engine algorithm – the examination of the page as a whole with consideration to the many words that were also common (semantically close) to the keywords. Thus, we now have, not only keyword and keyword phase searches, but also the added mix of words that are semantically close to the keywords and keyword phases. Surprisingly, this is how a human being looks at content, and mentally classifies a web page/document as a whole.

To put it all together, latent semantic indexing allows a search engine to determine what a page is about, without relying heavily on only keywords to draw the searcher to a web page. Even though keywords will still be relevant, the difference will be in how the search engines puts it all together. The search engines will not only analyze the keywords on a web page, but will consider the revelency of the keywords, as well as, the words that are semantically close in relation to the keywords and general theme of a page.

For example: web page for insurance – “health”, “auto”, “life” would be words related to the insurance theme.

Benefits and Drawbacks of Latent Semantic Indexing

With the change to LSI some will see benefits, while others will be having a hair-pulling awakening with a possible slip in page ranking.

Drawbacks

* For those who rely heavily on only one keyword, without any variation and without any additional words that relate directly to the theme of your page – you may see a drop.


Benefits

* With the increased relevancy and weight put on Latent Semantic Indexing, it can help to curtail “SEO black hat tactics”. With the old weighting system by Google, people could manipulate the search engines and obtain a rather decent page rank. With LSI, they will be a little hard pressed in determining which words or phases Google will place a higher or lesser relevancy in relation to the theme of the page.

*For those who have developed web pages that are filled with natural content, with keywords and keyword alternatives intermixed in their pages, they may not see much of a change. You may not consider it a benefit – but it certainly alleviates the headache and sleepless nights you may feel otherwise.


With the changes to LSI, I feel the emphasis for any webmaster will have to include:

* Quality content
* Keywords – keyword alternatives
* Mixed anchor text – and not just based on one keyword – but relevant to the content/theme of the web page.
* Variations of keyword/keywords and keyword phases – plural, singular or different tenses.
* Words that relate to the theme of the page


To conclude, the LSI introduction of Google to their search engines is, in my opinion, an attempt by Google to move the bar a little higher for quality content – not only emphasizing the most relevant, but also trying to emphasize the most useful information to it’s searchers. Where does that leave the webmaster? As always, when on the Internet -- expect change, and be ready to adapt and adjust to the changes when needed. And the other search engines – they may follow soon.

About the Author:
Vickie J Scanlon -- Visit her site at: myaffiliateplace.biz for tools, ebooks, "how to" affiliate/internet info, tech accessories, software and computers affiliate/small business person online.