# Hierarchical Grouping to Optimize an Objective Function

@article{Ward1963HierarchicalGT, title={Hierarchical Grouping to Optimize an Objective Function}, author={Joe H. Ward}, journal={Journal of the American Statistical Association}, year={1963}, volume={58}, pages={236-244} }

Abstract A procedure for forming hierarchical groups of mutually exclusive subsets, each of which has members that are maximally similar with respect to specified characteristics, is suggested for use in large-scale (n > 100) studies when a precise optimal solution for a specified number of groups is not practical. Given n sets, this procedure permits their reduction to n − 1 mutually exclusive sets by considering the union of all possible n(n − 1)/2 pairs and selecting a union having a maximal…

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