How Latent Semantic Indexing (LSI) Affects Search Engine Rankings

You may be scratching your head wondering what Latent Semantic Indexing is. It can really wreak havoc with search engine rankings and is something every SEO writer should be aware of.

What is Latent Semantic Indexing (LSI)?

Latent Semantic Indexing is basically a language algorithm that examines patterns of words for relational connectivity.

As an example, I’ll use a segment I saw on the TV crime show Forensic Files. In this particular episode, the deceased had supposedly left a suicide note. To determine if the note was indeed written by the deceased, a forensic language specialist examined it against known writings of his. 

By examining things like syntax, word patterns, use of language, etc., the specialist was able to determine if it was authored by him, or not. She determined that it was not.

Now, she also examined the suspect’s known writing samples and determined the suicide note had been written by him, not the deceased.

This is kind of how LSI works. In short, latent semantic indexing allows search engines to figure out what a page is about without matching exact search phrases. 

For example, If you write an article about types of apples you eat, by using LSI, the search engines will be able to differentiate it from an article about types of apple computers by the other language surrounding the word “apple.”

Ostensibly, an article about apple computers will contain phrases like iMac and computer, while an article about the types of apples you eat wouldn’t (ie, because of the relational connectivity between the words).

Why Latent Semantic Indexing Is Important to Making Money Online

In addition to the above, latent semantic indexing goes one step further. Instead of simply evaluating one document independently, LSI looks for relationships between sets of documents.

Eg, if you have a website about SEO marketing, it will scan that website looking for other pages that contain information relevant to that topic. It wouldn’t expect to find a page about quilting, for example.

As explained in detail on SEOBook.com:

 In addition to recording which keywords a document contains, the method examines the document collection as a whole, to see which other documents contain some of those same words. LSI considers documents that have many words in common to be semantically close, and ones with few words in common to be semantically distant.

This simple method correlates surprisingly well with how a human being, looking at content, might classify a document collection.[bold added] By placing additional weight on related words in content, or words in similar positions in other related documents, LSI has a net effect of lowering the value of pages which only match the specific term and do not back it up with related terms.

Read a full discussion of LSI.

The Future of Internet Marketing

The phrase bolded above is why latent semantic indexing is important. Search engine companies – particularly the larger ones like Google – are adopting technologies that make it harder for internet marketers to falsely rank high.

Proof? Read about the fallout over Google’s recent changes.

Once internet marketers figured out techniques to rank high in search engines – eg, keyword density, backlinking – it became easy to stuff an article with keywords, submit it to search engine directories and wait for the results to take effect. 

Why “Get-Rich-Quick Sites” Will Disappear from the Net (for a minute)

LSI makes it harder to do this. There are going to have to be more pages on a website, more text on a page, and more interconnectivity between them all for a site to rank high.

So, those sites with just a few stuffed with keywords and tons of ads will disappear (and the web community sends up a collective hallelujah).

The bottom line: Search engines owners want the web loaded with pages comprised of fresh, relevant, in depth, concise content. And many times, you have to wade through pages of results to find the meaningful ones because get-rich-quick gurus in every niche have figured out how to have their website pop up first when you type in a search phrase.

Like a new crime-fighting tool, LSI is the future of internet marketing technology in the SEO fight. UNTIL online criminals (ie, get-rich-quick gurus) figure out how to beat it. And the war rages on …

P.S.: Work from Home — Here’s How to Start a Social Media Consulting & Online Writing Biz

Here’s How to Start an Online Writing & Social Media Consulting Biz: Get all three ebooks for one low price and get started now.
Add to Cart

SM, SEO Writing, SM Biz Ebok Pkg

Be Sociable & Share