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

Chapter 7. Information Retrieval

Information Retrieval (IR) deals with finding information in unstructured data. Any data that has no specific or generalized structure is unstructured data, and processing such dataposes a great challenge to machines. Some examples of unstructured data are text files, doc files, XML files, and so on available on local PC or web. So, processing such large amount of unstructured data and finding the relevant information is a challenging task.

We will cover the following topics in this chapter:

  • Boolean retrieval
  • Dictionaries and tolerant retrieval
  • Vector space model
  • Scoring and term weighting
  • Inverse document frequency
  • TF-IDF weighting
  • Evaluation of information retrieval systems