Book Image

The Handbook of NLP with Gensim

By : Chris Kuo
Book Image

The Handbook of NLP with Gensim

By: Chris Kuo

Overview of this book

Navigating the terrain of NLP research and applying it practically can be a formidable task made easy with The Handbook of NLP with Gensim. This book demystifies NLP and equips you with hands-on strategies spanning healthcare, e-commerce, finance, and more to enable you to leverage Gensim in real-world scenarios. You’ll begin by exploring motives and techniques for extracting text information like bag-of-words, TF-IDF, and word embeddings. This book will then guide you on topic modeling using methods such as Latent Semantic Analysis (LSA) for dimensionality reduction and discovering latent semantic relationships in text data, Latent Dirichlet Allocation (LDA) for probabilistic topic modeling, and Ensemble LDA to enhance topic modeling stability and accuracy. Next, you’ll learn text summarization techniques with Word2Vec and Doc2Vec to build the modeling pipeline and optimize models using hyperparameters. As you get acquainted with practical applications in various industries, this book will inspire you to design innovative projects. Alongside topic modeling, you’ll also explore named entity handling and NER tools, modeling procedures, and tools for effective topic modeling applications. By the end of this book, you’ll have mastered the techniques essential to create applications with Gensim and integrate NLP into your business processes.
Table of Contents (24 chapters)
1
Part 1: NLP Basics
5
Part 2: Latent Semantic Analysis/Latent Semantic Indexing
9
Part 3: Word2Vec and Doc2Vec
12
Part 4: Topic Modeling with Latent Dirichlet Allocation
18
Part 5: Comparison and Applications

Latent Semantic Indexing with Gensim

In Chapter 4, Latent Semantic Indexing with scikit-learn, we learned about the construction of LSI from SVD and used scikit-learn to perform LSI. We also mentioned that the Gensim library has programmed LSI in a few lines of code for production purposes. In this chapter, we will build the LSI model with Gensim. We will also learn how to determine the right number of topics. I’ll also demonstrate to you how to put the model to real use as a search engine. This production-oriented perspective will help data scientists from non-NLP areas to consider stepping into the NLP world.

This chapter covers the following topics:

  • Performing text preprocessing
  • Performing text representation with BoW and TF-IDF
  • Modeling with Gensim
  • Using the coherence score to find the optimal number of topics
  • Understanding the final model
  • Using the model as an information retrieval tool

After completing this chapter, you will be able...