NLP lecture series, from basic to advance level- (Part-2)

(part-1), (part-2.1), (part-3), (part-4), (part-5), (part-6), (part-7), (part-8), (part-9), (part-10)

In the previous topic (part-1) we discussed about NLP introduction, usage, applications and linguistic tools. If you came directly to part-2, I recommend to check my part-1.

Document Retrieval

You might have visited any old library where the document retrieval system was based on catalog system and have seen how the librarians used to search a book for us but the advent of the world wide web has changed everything and everyone these days is a kind of document retriever and everyone knows about document search and its limitations.

Before going deeper…

image by author

NLP lecture series, from basic to advance level- (part-3)

Models that assign probabilities to sequences of words are called language models.

(part-1) ,(part-2), (part-2.1), (part-4), (part-5), (part-6), (part-7), (part-8), (part-9), (part-10)

Predicting future is difficult but how about predicting the next few words, immediately after the current word, for example:

Your program doesn’t _______? (work or allow or run … )
I like to eat Chinese _________? (food or cuisine or dumplings …)
She is my girl _______? (friend)
Please turn of your cell ________? (phone or membrane)

Hopefully, you can conclude which one is very likely next word. So, language modelling is about formalizing this intuition in machines…

Image by author

NLP lecture series, from basic to advance level- (part-2.1)

(Part-1) ,(Part-2), (Part-3), (Part-4), (Part-5), (Part-6), (Part-7), (Part-8), (Part-9), (Part-10)

This part is just for an additional content in this lecture series, you can skip this part if you want. If you have come directly here you can read more topics by clicking on above linked parts.

Probabilistic Retrieval

When we estimate how relevant a document is to a given query by feeding usual term and document frequency as parameters to a Bayesian model is termed as probabilistic retrieval or we can say in other terms it is an attempt to formalize the idea behind ranked retrieval in terms of probability theory.

image by author

NLP lecture series, from basic to advance level- (Part-1)

At the end of of this lecture series you will be:

  1. able to use major tools for text analysis,
  2. enough competent to do text preprocessing,
  3. skillful to extract features from texts,
  4. qualified to write your own NLP/IR programs,
  5. familiar with the fundamentals of NLP/IR,
  6. know the overview of most NLP/IR related research topics.

image by author

word2vec treats each word in corpus like an atomic entity and generates a vector for each word. In this sense Word2vec is very much like Glove — both treat words as the smallest unit to train on.

FastText (which is essentially an extension of word2vec model), treats each word as composed of character ngrams. So the vector for a word is made of the sum of this character n grams

Due to the enormous amount of data being generated by Facebook users every day, Facebook had a very challenging task to deal with such a huge amount of data. This…

Tatheer Hussain Mir

NLP Researcher| Ph.D. | Research focus “Social Networking and Human-Centered Computing”.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store