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

IRL

One of the biggest limitations of IL lies in its inability to learn other trajectories to reach a goal, except those learned from the expert. By imitating an expert, the learner is constrained to the range of behaviors of its teacher. They are not aware of the end goal that the expert is trying to reach. Thus, these methods are only useful when there's no intention to perform better than the teacher.

IRL is an RL algorithm, such as IL, that uses an expert to learn. The difference is that IRL uses the expert to learn its reward function. Therefore, instead of copying the demonstrations, as is done in imitation learning, IRL figures out the goal of the expert. Once the reward function is learned, the agent uses it to learn the policy.

With the demonstrations used only to understand the goal of the expert, the agent is not bound to the actions of the teacher and can finally...