Book Image

Statistics for Machine Learning

By : Pratap Dangeti
Book Image

Statistics for Machine Learning

By: Pratap Dangeti

Overview of this book

Complex statistics in machine learning worry a lot of developers. Knowing statistics helps you build strong machine learning models that are optimized for a given problem statement. This book will teach you all it takes to perform the complex statistical computations that are required for machine learning. You will gain information on the statistics behind supervised learning, unsupervised learning, reinforcement learning, and more. You will see real-world examples that discuss the statistical side of machine learning and familiarize yourself with it. You will come across programs for performing tasks such as modeling, parameter fitting, regression, classification, density collection, working with vectors, matrices, and more. By the end of the book, you will have mastered the statistics required for machine learning and will be able to apply your new skills to any sort of industry problem.
Table of Contents (16 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Cliff walking example of on-policy and off-policy of TD control


A cliff walking grid-world example is used to compare SARSA and Q-learning, to highlight the differences between on-policy (SARSA) and off-policy (Q-learning) methods. This is a standard undiscounted, episodic task with start and end goal states, and with permitted movements in four directions (north, west, east and south). The reward of -1 is used for all transitions except the regions marked The Cliff, stepping on this region will penalize the agent with reward of -100 and sends the agent instantly back to the start position.

The following snippets of code have taken inspiration from Shangtong Zhang's Python codes for RL and are published in this book with permission from the student of Richard S. Sutton, the famous author of Reinforcement Learning: An Introduction (details provided in the Further reading section):

# Cliff-Walking - TD learning - SARSA & Q-learning 
>>> from __future__ import print_function 
&gt...