Stepped hierarchy partition

Figure 5 An illustration of how a stepped hierarchy partition can extract particular clusters (clusters [8,1,2,3], [4,5], and [6,7], as shown below the hierarchy).

In fact, agglomerative procedures differ only by the way of updating the new distance matrix in each step. As an essentia drawback of hierarchic clustering, mistakes of fusion at a low level of aggregation are retained, due to hierarchy, in the whole sequence of partitions. 

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