Book Image

The Reinforcement Learning Workshop

By : Alessandro Palmas, Emanuele Ghelfi, Dr. Alexandra Galina Petre, Mayur Kulkarni, Anand N.S., Quan Nguyen, Aritra Sen, Anthony So, Saikat Basak
Book Image

The Reinforcement Learning Workshop

By: Alessandro Palmas, Emanuele Ghelfi, Dr. Alexandra Galina Petre, Mayur Kulkarni, Anand N.S., Quan Nguyen, Aritra Sen, Anthony So, Saikat Basak

Overview of this book

Various intelligent applications such as video games, inventory management software, warehouse robots, and translation tools use reinforcement learning (RL) to make decisions and perform actions that maximize the probability of the desired outcome. This book will help you to get to grips with the techniques and the algorithms for implementing RL in your machine learning models. Starting with an introduction to RL, youÔÇÖll be guided through different RL environments and frameworks. YouÔÇÖll learn how to implement your own custom environments and use OpenAI baselines to run RL algorithms. Once youÔÇÖve explored classic RL techniques such as Dynamic Programming, Monte Carlo, and TD Learning, youÔÇÖll understand when to apply the different deep learning methods in RL and advance to deep Q-learning. The book will even help you understand the different stages of machine-based problem-solving by using DARQN on a popular video game Breakout. Finally, youÔÇÖll find out when to use a policy-based method to tackle an RL problem. By the end of The Reinforcement Learning Workshop, youÔÇÖll be equipped with the knowledge and skills needed to solve challenging problems using reinforcement learning.
Table of Contents (14 chapters)
Preface
Free Chapter
2
2. Markov Decision Processes and Bellman Equations

Basics of Deep Learning

We have already implemented deep learning algorithms in Chapter 03, Deep Learning in Practice using TensorFlow 2. Before we begin with deep Q learning, which is the focus of this chapter, it is essential that we quickly revise the basics of deep learning.

Let us first understand what a perceptron is before we look into neural networks. The following figure represents a general perceptron:

Figure 9.1: Perceptron

A perceptron is a binary linear classifier, where the inputs are first multiplied by the weights, and then we take a weighted sum of all these multiplied values. Then, we pass this weighted sum through an activation function or step function. The activation function is used to convert the input values into certain values, such as (0,1), as output for binary classification. This whole process can be visualized in the preceding figure.

Deep feedforward networks, which we also refer to as Multilayer Perceptrons (MLPs...