Latent Semantic Indexing (LSI)is an ability by search engines to return results based upon a contextualisation algorithm. In simple terms humans understand that a mobilephone and a ringtone are related due to our experience of the world. What LSI allows a Search Engine to do is to move towards an ability to learn what words are related to other words. How does Latent Semantic Indexing Function? Latent Semantic Indexing functions based upon traditional keyword algorithms. I am being purposefully simplistic in this section so as only to focus on what you need to know. Currently a search engine will find your website by finding inbound links, links from other websites to your website, and following these to your site. When in your site The spider will read your code. From the code it will Index all the on and off screen content. From this it will make a table of keyphrases densities. This density is used in part of a Search Engine algorithm to determine a sites position in the search engine reults. Basically this is to give results where the phrase you searched for appear on the page. From the Links pointing to your site the target page will become more important for that term, in a very simplistic manner MSN uses this it appears as the corner stone for results . It is also central to Google and the other main search engines. How Does LSI Work? When the search engine visits a page it will determine from the content and links the focus of a page. Latent Semantic Indexing now means that secondary and tertiary page focus is important. Basically the search engine will realise that many pages on the internet which talk about optimization often talk about placement and positioning. The search engine now has the ability to understand that because many websites talk about these terms together that a Link exists between them. The more often that the words appear together the more related they are. From this set of gathered knowledge the Semantic Index is created. How can we see LSI In Action? In Google at present the LSI is visible in search results. If you conduct a search for 'phone' you will see that in the text snippets the word 'phone' is highlighted. If you search again using the search'~phone' the word that is now highlighted is 'Nokia'. Google has determined that Nokia is relevant to phone. Not all searches will return a semantic word set at present. What Does Latent Semantic Indexing mean for Your Website? Increasingly pages of keyword rich content look like pages of keyword rich content the keyphrase is repeated ad infinitum. You know the pages I mean. This kind of text will not help you fully penetrate your online market as the marketting aspect of your site is likely to be lost. By using semantically linked words to your central keyphrase you can vary the keyphrases while rasing your Keyword Density 'on the fly'. The semantic keyphrase does not appear to be treated with equal value but it will bring you the increase in keyword density which might otherwise not be available. In terms of site linking you can help your site whilst also increasing the keyword spread of your site. By varying the link text to a target page utilising the varied textual component you will get the benefit to all the semantically linked keyphrases. Semantic Indexing in future Search Engine Results. It is unlikely that in the short term semantic indexing will be key to sites positing as the central keyword focus and resulting relevancy will be of greater importance. However this will not fully filter through for some time to come. So if you start today getting your pages balanced and new links for related terms you may find your site is one step ahead of the game when/if the use of semantics in search engines is increased in power. The future of links from a semantic index base in Google is likely to become increasingly complex. If the algo rithm can be developed so that google can tell the semantic value of a site and pass this onto other related sites the issue of the manipulation of links will become more complex. Example: You want to rank for Search Engine Optimization traditionally you would want to get links from sites which were relevant for the term search engine optimization. Now what you can do is get links from important sites which may only rank for internet promotion but as Google knows they are related industry sites, semantically linked, the benefit is more than previously. Also any link from a site to a target site may take on some of the aspects of the page from which it is delivered i.e. link comes from a page important for the term 'Scotland' and this site then gives out a link to a partner and could increase the value of the target page for the term Scotland without mentioning the term in the link text. OK so I may be running away with the optimization benefits/problems of Latent Semantic Indexing when developing well positioned web sites and how far this may go. However it is something that all optimization specialists have to become aware of. Ethical SEO will rely on this part of the algorithm - as with all algo changes the goal is to improve the results to users of a search engine - the site which is returned is the most relevant. If you conduct ethical search engine positioning the advent of LSI will help as it will aid the removal of keyword spammers who try to rank sites using only narrow keyword sets and repeated phrases in the text. As usual it appears that Google has put itself at the forefront of search engine technology by being forward looking and investing in technology and a skill base ahead of the competition. Related resources Internet Consultancy - A web design service from Oyster Web to help you with your Internet strategy. Search Engine Optimization - Search Engine Optimization are part of our Internet marketing services that help create a successful web presence. Related Content Free Search Engine Positioning Report Article Source: http://www.oyster-web.co.uk/art-seo16.htm
He gave one example with "phone" and "nokia" but if you are looking for real life examples then you have to look hard to find them p.l.u.r.
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