Book Image

Hands-On Reinforcement Learning with Python

By : Sudharsan Ravichandiran
Book Image

Hands-On Reinforcement Learning with Python

By: Sudharsan Ravichandiran

Overview of this book

Reinforcement Learning (RL) is the trending and most promising branch of artificial intelligence. Hands-On Reinforcement learning with Python will help you master not only the basic reinforcement learning algorithms but also the advanced deep reinforcement learning algorithms. The book starts with an introduction to Reinforcement Learning followed by OpenAI Gym, and TensorFlow. You will then explore various RL algorithms and concepts, such as Markov Decision Process, Monte Carlo methods, and dynamic programming, including value and policy iteration. This example-rich guide will introduce you to deep reinforcement learning algorithms, such as Dueling DQN, DRQN, A3C, PPO, and TRPO. You will also learn about imagination-augmented agents, learning from human preference, DQfD, HER, and many more of the recent advancements in reinforcement learning. By the end of the book, you will have all the knowledge and experience needed to implement reinforcement learning and deep reinforcement learning in your projects, and you will be all set to enter the world of artificial intelligence.
Table of Contents (16 chapters)

Dueling network architecture

We know that the Q function specifies how good it is for an agent to perform an action a in the state s and the value function specifies how good it is for an agent to be in a state s. Now we introduce a new function called an advantage function which can be defined as the difference between the value function and the advantage function. The advantage function specifies how good it is for an agent to perform an action a compared to other actions.

Thus, the value function specifies the goodness of a state and the advantage function specifies the goodness of an action. What would happen if we were to combine the value function and advantage function? It would tell us how good it is for an agent to perform an action a in a state s that is actually our Q function. So we can define our Q function as a sum of a value function and an advantage function, as...