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

Training custom sequence labeling models

In this section, we will be looking at the process, syntax, objects, and methods involved in training custom sequence labeling models in Flair. If you read the previous sections of this chapter and understood the contents, you're in luck. Once you understand the underlying concepts of neural networks, have a GPU-equipped rig running, and are familiar with the most common parameters, the actual training process is actually fairly straightforward.

The process can be broken down into the following steps:

  1. Loading a tagged corpus
  2. Loading the tag dictionary
  3. Building the embedding stack
  4. Initializing the SequenceTagger object
  5. Training the model

Each of these steps requires only a few lines of code. To best understand the code, let's cover it as part of a practical example of training a PoS tagger. For example, let's pretend there are no pre-trained English taggers in Flair and attempt to train a PoS tagger...