Book Image

Natural Language Processing with Java - Second Edition

By : Richard M. Reese
Book Image

Natural Language Processing with Java - Second Edition

By: Richard M. Reese

Overview of this book

Natural Language Processing (NLP) allows you to take any sentence and identify patterns, special names, company names, and more. The second edition of Natural Language Processing with Java teaches you how to perform language analysis with the help of Java libraries, while constantly gaining insights from the outcomes. You’ll start by understanding how NLP and its various concepts work. Having got to grips with the basics, you’ll explore important tools and libraries in Java for NLP, such as CoreNLP, OpenNLP, Neuroph, and Mallet. You’ll then start performing NLP on different inputs and tasks, such as tokenization, model training, parts-of-speech and parsing trees. You’ll learn about statistical machine translation, summarization, dialog systems, complex searches, supervised and unsupervised NLP, and more. By the end of this book, you’ll have learned more about NLP, neural networks, and various other trained models in Java for enhancing the performance of NLP applications.
Table of Contents (19 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

The basics of LDA


LDA is the most popular method among the different methods of topic modeling. It is a form of text data mining and machine learning, where backtracking is performed to figure out the topic for the document. It also involves the use of probability, as it is a generative probabilistic model.

LDA represents the documents as a mixture of topics that will give a topic based on probability.

Any given document has a greater or lesser chance of having a certain word as its underlying topic; for example, given a document about sports, the probability of the word "cricket" occurring is higher than the probability of the word "Android One Phone". If the document is about mobile technology, then the probability of the word "Android One Phone" will be higher than the word "cricket". Using a sampling method, some words are selected from a document as a topic using Dirichlet distribution in a semi random manner. These randomly selected topics may not be the best suited as the potential...