Book Image

Hands-On Meta Learning with Python

By : Sudharsan Ravichandiran
Book Image

Hands-On Meta Learning with Python

By: Sudharsan Ravichandiran

Overview of this book

Meta learning is an exciting research trend in machine learning, which enables a model to understand the learning process. Unlike other ML paradigms, with meta learning you can learn from small datasets faster. Hands-On Meta Learning with Python starts by explaining the fundamentals of meta learning and helps you understand the concept of learning to learn. You will delve into various one-shot learning algorithms, like siamese, prototypical, relation and memory-augmented networks by implementing them in TensorFlow and Keras. As you make your way through the book, you will dive into state-of-the-art meta learning algorithms such as MAML, Reptile, and CAML. You will then explore how to learn quickly with Meta-SGD and discover how you can perform unsupervised learning using meta learning with CACTUs. In the concluding chapters, you will work through recent trends in meta learning such as adversarial meta learning, task agnostic meta learning, and meta imitation learning. By the end of this book, you will be familiar with state-of-the-art meta learning algorithms and able to enable human-like cognition for your machine learning models.
Table of Contents (17 chapters)
Title Page
About Packt


Hands-On Meta Learning with Python explains the fundamentals of meta learning and helps you to understand the concept of learning to learn. You will go through various one-shot learning algorithms, such as siamese, prototypical, relation, and memory-augmented networks, and implement them in TensorFlow and Keras. You will also learn about the state-of-the-art meta learning algorithms, such as model-agnostic meta learning (MAML), Reptile, and fast context adaptation via meta learning (CAML). You will then explore how to learn quickly with meta-SGD and discover how to perform unsupervised learning using meta learning. 

Who this book is for

This book will help machine learning enthusiasts, AI researchers, and data scientists who want to learn about meta learning as an advanced approach for training machine learning models. The book assumes a working knowledge of machine learning concepts and a sound knowledge of Python programming.

What this book covers

Chapter 1, Introduction to Meta Learning, helps us to understand what meta learning is and covers the different types of meta learning. We will also learn how meta learning uses few-shot learning by learning from a few data points. We will then see how to become familiar with gradient descent. Later in the chapter, we will see optimization as a model for the few shot learning setting.Chapter 2, Face and Audio Recognition Using Siamese Networks, starts by explaining what siamese networks are and how siamese networks are used in the one-shot learning setting. We will look at the architecture of a siamese network and some of the applications of a siamese network. Then, we will see how to use the siamese networks to build face and audio recognition models.Chapter 3, Prototypical Networks and Their Variants, explains what prototypical networks are and how they are used in the few shot learning scenario. We will see how to build a prototypical network to perform classification on an omniglot character set. Later in the chapter, we will look at different variants of prototypical networks, such as the Gaussian prototypical networks and semi-prototypical networks.

Chapter 4, Relation and Matching Networks Using TensorFlow, helps us to understand the relation network architecture and how relation network is used in one-shot, few-shot, and zero-shot learning settings. We will then see how to build a relation network using TensorFlow. Next, we will learn about the matching network and its architecture. We will also explore full contextual embeddings and how to build a matching network using TensorFlow.Chapter 5, Memory-Augmented Neural Networks, covers what neural Turing machines (NTMs) are and how they make use of external memory for storing and retrieving information. We will look at different addressing mechanisms used in NTMs and then we will learn about memory augmented neural networks and how they differ from the NTM architecture.Chapter 6, MAML and Its Variants, deals with one of the popular meta learning algorithms, called model-agnostic meta learning (MAML). We will explore what MAML is and how it is used in supervised and reinforcement learning settings. We will also see how to build MAML from scratch. Then, we will learn about adversarial meta learning and CAML, which is used for fast context adaptation in meta learning.Chapter 7, Meta-SGD and Reptile, explain how meta-SGD is used to learn all the ingredients of gradient descent algorithms, such as initial weights, learning rates, and the update direction. We will see how to build meta-SGD from scratch. Later in the chapter, we will learn about the reptile algorithm and see how it serves as an improvement over MAML. We will also see how to use the reptile algorithm for sine wave regression.Chapter 8, Gradient Agreement as an Optimization Objective, covers how we can use gradient agreement as an optimization objective in the meta learning setting. We will learn what gradient agreement is and how it can enhance meta learning algorithms. Later in the chapter, we will learn how to build a gradient agreement algorithm from scratch.Chapter 9, Recent Advancements and Next Steps, starts by explaining task-agnostic meta learning, and then we will see how meta learning is used in an imitation learning setting. Then, we will learn how we can apply MAML in an unsupervised learning setting using the CACTUs algorithm. Then, we will explore a deep meta learning algorithm called learning to learn in the concept space.

To get the most out of this book

You need the following software for this book:

  • Python
  • Anaconda
  • TensorFlow
  • Keras

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Conventions used

There are a number of text conventions used throughout this book.

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