Book Image

Machine Learning with R Cookbook, Second Edition - Second Edition

By : Yu-Wei, Chiu (David Chiu)
Book Image

Machine Learning with R Cookbook, Second Edition - Second Edition

By: Yu-Wei, Chiu (David Chiu)

Overview of this book

Big data has become a popular buzzword across many industries. An increasing number of people have been exposed to the term and are looking at how to leverage big data in their own businesses, to improve sales and profitability. However, collecting, aggregating, and visualizing data is just one part of the equation. Being able to extract useful information from data is another task, and a much more challenging one. Machine Learning with R Cookbook, Second Edition uses a practical approach to teach you how to perform machine learning with R. Each chapter is divided into several simple recipes. Through the step-by-step instructions provided in each recipe, you will be able to construct a predictive model by using a variety of machine learning packages. In this book, you will first learn to set up the R environment and use simple R commands to explore data. The next topic covers how to perform statistical analysis with machine learning analysis and assess created models, covered in detail later on in the book. You'll also learn how to integrate R and Hadoop to create a big data analysis platform. The detailed illustrations provide all the information required to start applying machine learning to individual projects. With Machine Learning with R Cookbook, machine learning has never been easier.
Table of Contents (21 chapters)
Title Page
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

The basics of neural network


Neural Network concepts relies on how the brain works. In simple terms, the brain is composed of large numbers of interconnected neurons working together to solve a specific problem. Neurons, in turn, are inter-connected with dendrites that produce output signals based on the inputs through an axon to another neuron. Neural nets are used to teach or rather a computer learns to perform a task by analyzing some training examples provided, like object or pattern recognition.

Getting ready

You should have completed previous recipes and understood them before completing this recipe.

How to do it...

In this example, we will provide training data of a number and its square root. Using neuralnet we will generate the square root of any number. Perform the following steps in R:

> install.packages('neuralnet')
> library("neuralnet")

Once the package is installed and loaded, we will create sample data of 50 numbers and their square roots in input and output. We combine both...