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

Chapter 5: Training Sequence Labeling Models

In this book, we have so far covered a number of features and models Flair offers right out of the box. The set of pre-trained sequence taggers, embeddings, and other models at first seems large enough for us to never need anything more than what's already available in Flair. But chances are, if you work with natural language processing (NLP) for long enough, you will encounter a problem that isn't generic enough to be solved by pre-trained models. When faced with such a problem, we usually need to train our own. This process involves acquiring training data, preprocessing it, possibly hand-labeling it, and finally, working with an NLP framework to train the model. But because Flair ships a wide selection of labeled corpora, chances are that you will only ever need to perform the last step, model training – the main focus of this chapter.

We will start this chapter by explaining when and why training custom models is...