Types of clustering

Cluster analysis is all about the kind of algorithms that can be used to find clusters automatically given the data. There are primarily two classes of clustering algorithm; they are as follows:

• The Hierarchical Clustering algorithms

• The Partitional Clustering algorithms

  

The Hierarchical clustering algorithms define clusters that have a hierarchy, while the partitional clustering algorithms define clusters that divide the dataset into mutually disjoint partitions.

Hierarchical clustering

The Hierarchical clustering is about defining clusters that have a hierarchy, and this is done either by iteratively merging smaller clusters into a larger cluster, or dividing a larger cluster into smaller clusters. This hierarchy of clusters that are produced by a clustering algorithm is called a dendogram. A dendogram is one of the ways in which the hierarchical clusters can be represented, and the user can realize different clustering based on the level at which the dendogram is defined...