Book Image

Machine Learning with R Cookbook

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

Machine Learning with R Cookbook

By: Yu-Wei, Chiu (David Chiu)

Overview of this book

<p>The R language is a powerful open source functional programming language. At its core, R is a statistical programming language that provides impressive tools to analyze data and create high-level graphics.</p> <p>This book covers the basics of R by setting up a user-friendly programming environment and performing data ETL in R. Data exploration examples are provided that demonstrate how powerful data visualization and machine learning is in discovering hidden relationships. You will then dive into important machine learning topics, including data classification, regression, clustering, association rule mining, and dimension reduction.</p>
Table of Contents (21 chapters)
Machine Learning with R Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Resources for R and Machine Learning
Dataset – Survival of Passengers on the Titanic
Index

Classifying data with gradient boosting


Gradient boosting ensembles weak learners and creates a new base learner that maximally correlates with the negative gradient of the loss function. One may apply this method on either regression or classification problems, and it will perform well in different datasets. In this recipe, we will introduce how to use gbm to classify a telecom churn dataset.

Getting ready

In this recipe, we continue to use the telecom churn dataset as the input data source for the bagging method. For those who have not prepared the dataset, please refer to Chapter 5, Classification (I) – Tree, Lazy, and Probabilistic, for detailed information.

How to do it...

Perform the following steps to calculate and classify data with the gradient boosting method:

  1. First, install and load the package, gbm:

    > install.packages("gbm")
    > library(gbm)
    
  2. The gbm function only uses responses ranging from 0 to 1; therefore, you should transform yes/no responses to numeric responses (0/1):

    &gt...