Book Image

Rapid - Apache Mahout Clustering designs

Book Image

Rapid - Apache Mahout Clustering designs

Overview of this book

Table of Contents (16 chapters)
Apache Mahout Clustering Designs
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Learning Fuzzy K-means clustering


Fuzzy K-means clustering is a fuzzy form of the K-means algorithm that we discussed earlier. Fuzzy K-means generate soft clusters, in which a point can belong to more than one cluster and will have a valid affinity in that cluster. Fuzzy K-means is helpful in defining the relationship between the different data points. It is good for clustering text documents. This algorithm takes similar parameters as K-means, except for one additional fuzziness factor. Fuzzy K-means iterates over the dataset and calculates a degree of association of each point to each of the clusters. So, the degree of association happens in this way—suppose that we have centroids c1, c2, and c3, and we have distances d1, d2, and d3 for a vector V from centroids c1, c2, and c3.

The degree of association for centroid c1 will be calculated as:

Here, k is the number of centroids and m is the fuzziness factor. In the same way, we can calculate the degree of association with other centroids after...