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

Manipulating data with plyrmr


While writing a MapReduce program with rmr2 is much easier than writing a native Java version, it is still hard for non-developers to write a MapReduce program. Therefore, you can use plyrmr, a high-level abstraction of the MapReduce program, so that you can use plyr-like operations to manipulate big data. In this recipe, we will introduce some operations you can use to manipulate data.

Getting ready

In this recipe, you should have completed the previous recipes by installing plyrmr and rmr2 in R.

How to do it...

Perform the following steps to manipulate data with plyrmr:

  1. First, you need to load both plyrmr and rmr2 into R:
> library(rmr2)> library(plyrmr)
  1. You can then set the execution mode to the local mode:
> plyrmr.options(backend="local")
  1. Next, load the Titanic dataset into R:
> data(Titanic)> titanic = data.frame(Titanic)
  1. Begin the operation by filtering the data:
> where(+    Titanic, + Freq >=100)
  1. You can also use a pipe operator to filter the...