Book Image

Natural Language Processing with Flair

By : Tadej Magajna
Book Image

Natural Language Processing with Flair

By: Tadej Magajna

Overview of this book

Flair is an easy-to-understand natural language processing (NLP) framework designed to facilitate training and distribution of state-of-the-art NLP models for named entity recognition, part-of-speech tagging, and text classification. Flair is also a text embedding library for combining different types of embeddings, such as document embeddings, Transformer embeddings, and the proposed Flair embeddings. Natural Language Processing with Flair takes a hands-on approach to explaining and solving real-world NLP problems. You'll begin by installing Flair and learning about the basic NLP concepts and terminology. You will explore Flair's extensive features, such as sequence tagging, text classification, and word embeddings, through practical exercises. As you advance, you will train your own sequence labeling and text classification models and learn how to use hyperparameter tuning in order to choose the right training parameters. You will learn about the idea behind one-shot and few-shot learning through a novel text classification technique TARS. Finally, you will solve several real-world NLP problems through hands-on exercises, as well as learn how to deploy Flair models to production. By the end of this Flair book, you'll have developed a thorough understanding of typical NLP problems and you’ll be able to solve them with Flair.
Table of Contents (15 chapters)
1
Part 1: Understanding and Solving NLP with Flair
6
Part 2: Deep Dive into Flair – Training Custom Models
11
Part 3: Real-World Applications with Flair

Understanding text classification

Text or document classification is simply a process of assigning one or more labels (often called classes) to a piece of text (often called a document). A text classifier is a machine learning model that receives some text as input and computes a probability distribution over a set of classes.

Text classification has many real-world uses and is actively used to solve the following problems:

  • Topic classification – the process of assigning a topic to a document
  • Spam detection – the process of detecting unwanted emails
  • Sentiment analysis – classifying text sentiment into positive and negative
  • Hate speech detection – identifying hate speech in text
  • Language identification – figuring out what language a document is written in

Here's an example of the real world use of text classification:

Figure 8.1 – Spam detection

In relation to how documents are...