Book Image

Reinforcement Learning Algorithms with Python

By : Andrea Lonza
Book Image

Reinforcement Learning Algorithms with Python

By: Andrea Lonza

Overview of this book

Reinforcement Learning (RL) is a popular and promising branch of AI that involves making smarter models and agents that can automatically determine ideal behavior based on changing requirements. This book will help you master RL algorithms and understand their implementation as you build self-learning agents. Starting with an introduction to the tools, libraries, and setup needed to work in the RL environment, this book covers the building blocks of RL and delves into value-based methods, such as the application of Q-learning and SARSA algorithms. You'll learn how to use a combination of Q-learning and neural networks to solve complex problems. Furthermore, you'll study the policy gradient methods, TRPO, and PPO, to improve performance and stability, before moving on to the DDPG and TD3 deterministic algorithms. This book also covers how imitation learning techniques work and how Dagger can teach an agent to drive. You'll discover evolutionary strategies and black-box optimization techniques, and see how they can improve RL algorithms. Finally, you'll get to grips with exploration approaches, such as UCB and UCB1, and develop a meta-algorithm called ESBAS. By the end of the book, you'll have worked with key RL algorithms to overcome challenges in real-world applications, and be part of the RL research community.
Table of Contents (19 chapters)
Free Chapter
1
Section 1: Algorithms and Environments
5
Section 2: Model-Free RL Algorithms
11
Section 3: Beyond Model-Free Algorithms and Improvements
17
Assessments

Imitation Learning with the DAgger Algorithm

The ability of an algorithm to learn only from rewards is a very important characteristic that led us to develop reinforcement learning algorithms. This enables an agent to learn and improve its policy from scratch without additional supervision. Despite this, there are situations where other expert agents are already employed in a given environment. Imitation learning (IL) algorithms leverage the expert by imitating their actions and learning the policy from them.

This chapter focuses on imitation learning. Although different to reinforcement learning, imitation learning offers great opportunities and capabilities, especially in environments with very large state spaces and sparse rewards. Obviously, imitation learning is possible only when a more expert agent to imitate is available.

The chapter will focus on the main concepts and...