Comprehensive Study of Hierarchical Clustering Algorithm and Comparison with Different Clustering Algorithms

Suppose that you have a set of data objects for analysis, in that the class label of each object is not knows. Then how can you do the classification of this data object..? Clustering is the process of grouping the data into classes or says clusters so that objects within a cluster have high similarity in comparison to one another, but are very dissimilarity to objects in other clusters. This process of groping a set of physical or abstract objects into classes of similar objects is called clustering. Thus we can say that clustering is unsupervised method of classification. As a data mining function, cluster analysis can be used as a standalone tool to gain insight into the distribution of data, to observe the characteristics of each cluster, and to focus on a particular set of clusters for further analysis.