Any online business owner who plans to use SEO techniques should be aware of exactly what Latent Semantic Indexing is, how it influences the text on website pages, and why it is an important concept to understand and utilise.
Let’s take a look at the definition of LSI and how it can work to your advantage.
Latent Semantic Indexing Defined
Although you may already know what it is, let’s define the term and ensure that you have a strong grasp of the technique. Latent Semantic Indexing, or LSI, refers to using phrases and words that are related to the subject about which you are writing.
These related terms should be sprinkled throughout the text. For instance, if your website sells women’s shawls, you would want to add some descriptive and alternative terms to your page text which might include “pashmina”, “lamb’s wool”, “silk”, “fringed scarves”, “evening wraps”, etc. All of these words and phrases are closely and semantically related to the topic of shawls and might be used by the average consumer who is performing an internet search to find your product.
The key word in the above definition is “semantic”. Latent Semantic Indexing does not refer to using the plural of your main word. “Shawls” is not technically a word semantically related to “shawl”. This gives no greater meaning to the content on your page.
How LSI And Search Engines Are Related
Why is it important to include semantically related terms? The number one reason is that major search engines such as Google and Yahoo utilise particular techniques that allow users to enjoy “smart” searches.
Savvy computer users know that using the tilde symbol (~) instructs the search engine to return listings of web pages with content related semantically to the search term typed after the tilde (i.e. ~shawl).
Such things as capitalisation and context come into play to ensure that web surfers are treated to relevant results when searching. Popularity also comes into play. Because more people surfing the net will perform a search for “Apple” that actually refers to the computer company and not the fruit, Google results will return a listing for sites related to a Macintosh, iPhone, or iPod first.
The more related terms you include in your text, the better your chance that a web crawler will find your website and include it in searches for phrases that are related to your content. If someone inputs the word “light” in the search box, they could be looking for information on indoor illumination, on low-calorie food, or something that fires up their cigar. If your website sells light bulbs, then you will want to post text that includes terms such as wattage, chandelier, lamps, lighting fixtures, etc. But if you are a seller of diet food, then your LSI will revolve around such phrases as, low calorie, diet plans, weight loss and the like.
You should easily be able to see how the plural “lights” would do little to help Google determine the exact subject matter of your website. Lights could refer to either more than one bulb or match.
The more you use LSI, the greater your chances that Google or Yahoo will correctly categorise your web pages and their content, and rank them accordingly. There are some software programs that allow you to easily determine related keywords and even some online resources that will do so for free.
Try doing a search of related terms and see if, and where, your website comes up in the results listing. If your ranking is unacceptable, consider rewriting your page text to include relevant Latent Semantic Indexing.
See you at the top of Google!
Sean Rasmussen
SEO Australia Pacific
AussieSEO.com © 2007 - 2010
Hi Sean,
I think I could be doing better with my use of latent semantic indexing. Is this why you have some different words highlighted in your post, rather than just your keyword ‘latent semantic indexing’?
Do you highlight the extra words to indicate to the search engines that these words are also highly relevant to your keywords? Or, do I have this wrong?
I think you will find the target keyphrase for this article is “latent semantic indexing” Jazz. I can’t see any other highlighted phrases or words in there. There is no need to highlight related words, just the fact that they are included is fine.
Hi Sean,
I was asking about the words, ‘SEO, search engines and keywords’ specifically. All three are written in blue and underlined. I was just wondering why you do it?
I don’t do this and I feel like I should be, just because you do it. How does doing this help my SEO? I hope this makes more sense.
Hi Sean,
I’m really sorry, Sean. Please forgive my silly question. I can see you’re linking to other posts. I was just having a blonde moment.
All good Jazz, linking to other posts is good for SEO as well as providing further relevant information for the reader
That’s fascinating. I just tried out the tilde with some searches and the results are astoundingly different comparing with and without tilde. I am going to focus much more now on including Latent Semantic Indexing in my post designs.
.-= Wal Heinrich´s last blog ..Cheapest Granny Flats In Australia =-.
So it’s called LSI, thanks Sean.
I have always tried to include relevant keywords in my posts to support and bring weight to the primary keyword being targeted in that particular post. I have attempted to use keyword proximity and density without being overbearing. So hopefully this will all pay off one-day.
.-= Cemil´s last blog ..Scribe SEO Plugin – Making SEO Easy =-.
Hey Sean,
Just learnt something new (well, two things, to tell the truth) and upped my computer saviness by a notch! Was unaware of ANY use for the tilde, let alone in searches. And your definition of LSA and the examples, as usual, were very simple and clear!
Cheers,
Pete
I was the same Pete never knew what the use for ~ or what Tilde, was now I know its use and a very helpful one at that.
Well this old dog learned a new trick on reading this article on “Latent Semantic Indexing”. The use of the tilde for a search. I just tried it and got almost totally different results. I’ll have to pass that tip along to my wife.
When working with clients I try to instill in them the importance of semantically related words throughout the content of their pages. Now I’ll be able to illustrate the different results people will get when searching. Nice tip.
.-= Don White´s last blog ..Psycho- =-.
Hi Sean
Just used the tilde on a search and yes, the difference is remarkable. Interesting how one little change can make a huge change.
Knowing about LSI will be a great advantage to all of us for embellishing our blogs with words that relate to our subject matter, as long as it doesn’t interrupt the comprehensive flow of the post.
Thankyou.
.-= Elly´s last blog .. =-.
Hi Sean,
I have read this article before and it didn’t comprehend. I can understand much better this time. I now understand the meaning of “Latent Semantic Indexing” It’s a real advantage for me to now understand the meaning of LSI and how to put it into practice.
Also, I had not heard the name Tilde before. At times I had wondered what the symbol meant though. Great tip Sean. Thanks.
.-= Jill Brown´s last blog ..Couples Marry at Common Law =-.
Hi Sean,
I first thought that if I write a good qualitiy article that this would take care of Latent Semantic Indexing by itself. But I guess everybody uses language a bit different and it pays to check out (by using the tilde as you explained) how the search engines “think” and what they consider relevant connected words.
So, even more keyword research from now on
.-= Renee´s last blog ..Self Improvement – 25 Self Motivation Quotes =-.
In many ways Renee, good writing will cover some of the LSI factors (e.g. using synonyms). What this article does is take that further in explanation – as a checklist almost.
Latent Semantic Indexing , I never would have figured this one out Sean….now I see why you can Rank #1 on Google in under 20 minutes…
This is an excellent explanation of Latent Semantic Indexing – which is so crucial for indexing and keywords.
I mentioned somewhere else that I wrote an article called “Latent Semantic Indexing Technique” – and it ranks #1 on Google page 1. A search for “Latent Semantic Indexing” brings up my article at #10 on page 1 – which goes to show how a little longer tail works better.
I am not writing this to brag – but because I can’t work out why my article, or even for the title of this blog “Tips on Latent Semantic Indexing” brings up my article at #3 spot and not this actual article which is SO much better an explanation of LSI than mine.
Copy this article as it is the best one you will find.
Congratulations on your ranking Peter, well done
. I write so many articles, I don’t get to build backlinks to them all, this would be one of the reasons mine is not ranking so well. Glad you enjoyed it anyway 
I can understand why you don’t have time Sean! I am going to work out how to get yours there somehow if I can
Sounds good to me Peter! Cheers mate
I will definitely be working at using LSI in my writings. I have a lot of work to do on them. While I write well, that isn’t good enough. Thank you, Sean. All the things I’m learning from you are priceless to me.
As a person who writes well, I bet you will find that you do more LSI automatically than you realise! It may just be matter of being a little more conscious of it and doing some keyword tweaking. Good writers often use synonyms, reverse order of phrases etc just as a matter of the habit of good writing.
This article on Tips on Latent Semantic Indexing is the best you will find
LSI is also a really great way to reduce your KW density if you are finding that it is too high. I would assume too that it would also help the adsense network put more relevants ads on your page as it understands your content better. A good example would be Apple – fruit or IT company? The use of LSI here would be crucial.
.-= Jayne Pleysier´s last blog ..How A Marketing Service Can Help Your Business Grow =-.
That’s worth pointing out Jayne. LSI is contextual and it does affect the quality of the content by its very nature linguistically. As such then it should attract good adsense – more so if the keywords are high value ones.