Book Image

Mastering Machine Learning with R

By : Cory Lesmeister
Book Image

Mastering Machine Learning with R

By: Cory Lesmeister

Overview of this book

Table of Contents (20 chapters)
Mastering Machine Learning with R
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Modeling and evaluation


Having created our data frame, df, we can begin to develop the clustering algorithms. We will start with hierarchical and then try our hand at k-means. After this, we will need to manipulate our data a little bit to demonstrate how to incorporate mixed data and conduct PAM.

Hierarchical clustering

To build a hierarchical cluster model in R, you can utilize the hclust() function in the base stats package. The two primary inputs needed for the function are a distance matrix and the clustering method. The distance matrix is easily done with the dist() function. For the distance, we will use Euclidean distance. A number of clustering methods are available and the default for hclust() is the complete linkage. We will try this, but I also recommend Ward's linkage method. Ward's method tends to produce clusters with a similar number of observations.

The complete linkage method results in the distance between any two clusters that is the maximum distance between any one observation...