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

How cosine similarity is used in images

Any digital images can be converted into vectors. The vectors can be compared in the latent vector space by the cosine similarity score to indicate the “resemblance” of two images. Figure 5.2 first shows the digital image of the number 5 as a 2D matrix.

Figure 5.2 – The image of “5” (image from [1])

Figure 5.2 – The image of “5” (image from [1])

This 2D matrix can be converted by a neural network such as a Convolutional Neural Network (CNN) to become vectors. The square boxes in Figure 5.2 represent a series of layers, including convolutional, pooling, and fully connected layers, to convert an image to a long vector. Let me describe the process a little bit. Initially, the CNN applies multiple convolutional layers to extract hierarchical features from the image. These layers detect patterns such as edges, textures, and shapes. As the network progresses through convolution and pooling layers, it captures increasingly complex...