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In the World of Document Similarity

How does a human infer whether two documents are similar? This question has dazzled cognitive scientists, and is one area under which a lot of research is taking place. As of  now there is no product that is able to match or surpass human capability in finding the similarity in documents. But things are improving in this domain, and companies such as IBM and Microsoft are investing a lot in this area.

We at Cere Labs, an Artificial Intelligence startup based in Mumbai, also are working in this area, and have applied LDA and Word2Vec techniques, both giving us promising results:

Latent Dirichlet Allocation (LDA): LDA is a technique used mainly for topic modeling. You can leverage on this topic modeling to find the similarity between documents. It is assumed that more the topics two documents overlap, more are the chances that those documents carry semantic similarity.

You can study LDA in the following paper:

You can implement LDA using Gensim:

Word2Vec:

Word2Vec bring words into vector space, where words with similar semantic meaning are embedded near each other. So when plotted in a higher dimensional vector space, similar words tend to come together. The best part with Word2Vec is that it also captures semantic similarity.

You can read the original Word2Vec paper here:

You can also check the implementation in tensorflow at:

Both LDA and Word2Vec techniques can be combined to achieve interesting results. Keep following this space as we will report our findings in future blog posts.

When we look at the results achieved by such techniques, it feels that the AI is thinking. 

For a detailed understanding of Word Embeddings please refer to the following article - An Introduction to Word Embeddings


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