LATENT SEMANTIC INDEXING (LSI)

In the world of search engines, a well-chosen result is king. Indexing as a science has become highly targeted. Today we can search a term on Google and get pages of results that are optimized to the exact word or term. In the push for the most natural and useful search results per page, Google has now brought the revolutionary latent semantic indexing (LSI) to its algorithms.

Defining LSI

Latent Semantic Indexing, or LSI, is the completely unique method of indexing web search results in an entirely new way. With this algorithm, Google has taken the previously cold and mechanical search engine result and moved it another rung up the ladder towards a more human way to rank page results. If a web user was to undertake a search manually, the results generated would be most likely to be based on the theme and content of the site rather than the number of instances of a word appearing on the page or determining whether the searched-for word exists on the site at all.

The Effect of LSI

With the introduction LSI, web searches have experienced a change in how results are calculated. The shift it has caused among top sites who have previously performed well- thanks to a single-keyword delivered ranking- have found their pages slipping down the rankings. Diversely worded pages with a varied selection of inbound links are on the rise with search term results that previously would never have performed half as well.

Although LSI has changed the face of web search ranking, the field of SEO is still very much alive. Writing website copy exclusively for Google is not just stitched together from keyword densities and placement; outdated methods of writing and link-building are ready to move forward, incorporating LSI algorithms.

LSI, SEO and you

The effect latent semantic indexing will have on any given web page is almost entirely dependent on how the webmaster regularly promotes their site. A page that features natural content that includes elements such as keywords and keyword alternative and boasts a link profile with diversification in the same vein for a decent amount of related keywords; then the ranking of the page won't be affected by LSI in the way a page containing a larger proportion of a single on-page or off-page keyword will be. Achieving a natural balance of well chosen keywords can greatly change the rank of your page in a given search.

The Necessity of LSI in Search Engines

Previously, inflexible "keyword indexing" meant that the techniques favored by black hat SEOs were easier to execute. A page ranking could be manipulated up the list by jamming a page full of a set of keywords, a manipulation that saw many pages reach top rankings. Later, reciprocal linking made it possible to manipulate search engine spiders by exchanging links with thousands of sites. The practice of reciprocal linking was eventually beaten by the big search engines giving it less credence than a one-way inbound link. Today, LSI is the latest answer to rank manipulating code working hard to bring more naturally relevant search results.

Reviewing your Link Profile

Scrutinize your link profile; does it consist of many links with your primary keyword as identical anchor text? If your profile is already full to brimming with this consider changing over to relevant and similar terms that will immediately improve your link profile.

Creating written LSI content

Consider the structure of a sentence as it will apply to your page. Optimizing a page specifically for Google will allow you to write naturally with language that comes, well, naturally. When writing, we include appropriate keywords in the body copy. To avoid repetition (or keyword optimization), we instinctively know to alter the instances of keywords for synonyms that hold similar meaning. Our brains will tell us that by experimenting with tenses, stems and including plural and singular forms of a word we can avoid dreaded replication.

The LSI Benefits for Web Searchers

Most people using web search engines find that LSI offers a distinct improvement over previous forms of search engine indexing. They see it will understand word strings as having a different meaning from each singular word: an LSI sees the phrase search engine optimization and will distinguish its meaning from other searchable terms like steam engine or locomotive engine and leave these out of search results. The theory behind this distinctive search term is to provide more accurate search results while supplying a wider range geared towards the original search topic.

Google, clearing the path for others

We've already discussed the leaps and bounds Google is taking now into the future of latent semantic indexing. The search engine employs the LSI algorithm to generate search results that are reliably full of genuine results that searchers can go to immediately, and provide a unique service that will bring them back. Competitors such as Yahoo and MSN still use traditional keyword specific indexing to determine search results, although now Yahoo's search algorithm will review keyword stemming as well as singular and plural variations when determining word density.

With the future of search engines becoming brighter, the benefits of latent semantic indexing are multi-fold, leading the way for even more reliable searches and greater volumes of relevant information gathering.