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Latent Semantic Indexing

Updated: Sep 1, 2023

If you are a copywriter and have been trying to rank your content on Google, then you have come face to face with the much-talked-off algorithm RankBrain. Why discuss the algorithm? The interesting part is that this algorithm relies much on LSI keywords. During the early days of the search engine, Google used a technique called Page Rank, which depended much on the backlinks and keywords in the content that matched the searched query.

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With time and more advancement with searches, there were nearly 15% of fresh keyword searches every day which meant Google would take longer to find the relevant stuff and may also tend to return irrelevant content. To overcome this gap, Google introduced a new ranking algorithm that was based on Artificial Intelligence and Machine Learning techniques. This meant it kept track of not only the searched terms but also related keywords and phrases which fell under the category of LSI keywords.

Latent Semantic Indexing means hidden keywords with similar meaning or intent as the searched terms. For instance when a user searches for "You are an owl" It actually means "You are a bird" but the literal meaning says "You are a nocturnal animal" or "You are a fool". As humans, it is well understood, but machines need to understand the hidden intent of the words and phrases. This is well handled by the RankBrain algorithm. Having known that the Google searches depend on LSI keywords it becomes of utmost importance that the content must be created around these keywords without indulging in stuffing and spamming.

LSI technology originated from LSA (Latent Semantic Analysis) which was patented in 1988 during the initial days of the internet which then expired in 2008. However Google has denied the use of LSI, but it is evident that a similar yet more advanced algorithm must have been incorporated by Google which does identify related keywords and phrases based on synonyms and intent. However, this advanced algorithm also has the ability to improvise based on past searches. This gives way to the fact that it would be good to incorporate LSI keywords into your content while optimizing.

Originally LSA was used for concept searches and categorization of documents which gradually made its way to Search Engine Optimization.

There are three forms of LSI keywords in use

  • synonyms

  • substitution

  • sentimental and logically related words and phrases

The tools mentioned in "5 FREE Keyword Tools" will help identify the LSI keywords other than these, below are a few more free tools that can identify semantic keywords around the main or head keyword. It can also give related phrases for the seed keywords. To know more about keywords and their types check the article "Types of Keywords".

Along with the above tools Google Related Search terms found at the bottom of the results page or the Semrush keyword magic tools can also be used in their free versions. The intent of identifying these keywords is to build content around them so that Google's algorithm identifies the relevancy of your content with the related keywords and phrases. This will boost your page rank while decreasing the bounce rate of your page. The relevancy of the content to the related keywords will also roll out the possibility of spammed content.

To know more about SEO and related topics in Digital Marketing check other articles.

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