If one examines in Wikipedia you will find that LSI is Latent Semantic Indexing LSI is a retrieval method that uses a mathematical technique called singular value decomposition (SVD) to identify patterns in relationships between concepts and concepts that exist in an unstructured text.
The principles LSI is based on is the that the words used in similar contexts often have an identical meaning. To an article writer or an affiliate marketer it is not necessary to know how SVD works. However it's important for you to the have knowledge about keyword research and to know what LSI keywords is and how you can use them in your article writing and affiliate marketing.
In the SEO (search engine optimization) you use the targeted keywords on your page, that way you seek search engine to rank you high on the page. Keywords are important in affiliate marketing and you have to know what to do to get the best possible result, it is important not to use too many keywords because this can count as spamm and you will not get the good position on this page you want
Here, is where LSI keywords come into its rightful use, if you use the LSI keywords in your article instead of too many "common" keywords, the effect is positive in that you're covering the most important keywords without having to use too many spammy once, this will appear good to your readers eyes.
Where do youfind these LSI keyword tool?
Go to Google Adwords tools. Search "Google Ad Words search tool". Enter the keyword in the text box and then captha and click on "Get keyword ideas" - button This will bring up a list of keywords, this is the LSI Keywords which you can you can use and they will help you achieve higher rankings in search engines.