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

Performing nonlinear dimension reduction with ISOMAP


ISOMAP is one of the approaches for manifold learning, which generalizes linear framework to nonlinear data structures. Similar to MDS, ISOMAP creates a visual presentation of similarities or dissimilarities (distance) of a number of objects. However, as the data is structured in a nonlinear format, the Euclidian distance measure of MDS is replaced by the geodesic distance of a data manifold in ISOMAP. In this recipe, we will illustrate how to perform a nonlinear dimension reduction with ISOMAP.

Getting ready

In this recipe, we will use the digits data from RnavGraphImageData as our input source.

How to do it...

Perform the following steps to perform nonlinear dimension reduction with ISOMAP:

  1. First, install and load the RnavGraphImageData and vegan packages:

    > install.packages("RnavGraphImageData")
    > install.packages("vegan")
    > library(RnavGraphImageData)
    > library(vegan)
    
  2. You can then load the dataset, digits:

    > data(digits)...