Book Image

Hands-On Q-Learning with Python

By : Nazia Habib
Book Image

Hands-On Q-Learning with Python

By: Nazia Habib

Overview of this book

Q-learning is a machine learning algorithm used to solve optimization problems in artificial intelligence (AI). It is one of the most popular fields of study among AI researchers. This book starts off by introducing you to reinforcement learning and Q-learning, in addition to helping you become familiar with OpenAI Gym as well as libraries such as Keras and TensorFlow. A few chapters into the book, you will gain insights into model-free Q-learning and use deep Q-networks and double deep Q-networks to solve complex problems. This book will guide you in exploring use cases such as self-driving vehicles and OpenAI Gym’s CartPole problem. You will also learn how to tune and optimize Q-networks and their hyperparameters. As you progress, you will understand the reinforcement learning approach to solving real-world problems. You will also explore how to use Q-learning and related algorithms in scientific research. Toward the end, you’ll gain insight into what’s in store for reinforcement learning. By the end of this book, you will be equipped with the skills you need to solve reinforcement learning problems using Q-learning algorithms with OpenAI Gym, Keras, and TensorFlow.
Table of Contents (14 chapters)
Free Chapter
1
Section 1: Q-Learning: A Roadmap
6
Section 2: Building and Optimizing Q-Learning Agents
9
Section 3: Advanced Q-Learning Challenges with Keras, TensorFlow, and OpenAI Gym

Chapter 6, Digging Deeper into Deep Q-Networks with Keras and TensorFlow

  1. Keras abstracts many of the functionalities provided by TensorFlow and creates a high-level frontend for creating complex deep learning architectures.
  2. CartPole is effectively a binary prediction problem because there are two options provided for every action taken.
  3. When the state space is very large, some states can be grouped together and treated similarly when the optimal actions to take from those states are the same.
  1. Experience Replay updates the Q-function using samples of past actions rather than updating it after every action. This helps prevent overfitting by smoothing away outlier actions and having the agent forget previous experiences in favor of new ones.
  2. An RL model approximating Q-values does not know what those actual Q-values are and progressively develops estimates for those values. A...