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 Dirichlet Allocation

When we write an article, we develop it according to a theme or topic and we use certain words from that topic. We may have sub-topics and use the words for the sub-topics too. When we classify articles into topic piles, we recognize specific words and then tag them so that we can place them into topics. An article may have one topic and other sub-topics, so it is possible to tag an article to multiple topics. Latent Dirichlet Allocation (LDA) is designed to discover abstract topics in a document. This makes LDA a powerful model that can tag an article with multiple topics.

LDA is the core technique in NLP and is worth investigating thoroughly. It has enabled many commercial products. The knowledge of LDA, such as its architecture, its use of the generative modeling process, and Dirichlet distribution, are transferable to other models. For these reasons, this book has dedicated four chapters to LDA: Chapter 9, Understanding Discrete Distributions which...