手法を比較

	Mean Shift	階層的クラスタリング
分野	機械学習	機械学習
系統	Machine learning	Machine learning
提唱年	1975	1963
提唱者	Fukunaga, K. & Hostetler, L. D.; extended by Comaniciu, D. & Meer, P.	Ward, J. H.
種類	Non-parametric mode-seeking / density-based clustering	Unsupervised clustering (agglomerative)
原典	Fukunaga, K. & Hostetler, L. D. (1975). The estimation of the gradient of a density function, with applications in pattern recognition. IEEE Transactions on Information Theory, 21(1), 32–40.	Ward, J. H. (1963). Hierarchical Grouping to Optimize an Objective Function. Journal of the American Statistical Association, 58(301), 236–244.
別名	mean-shift clustering, mean shift mode seeking, kernel mean shift, nonparametric mode detection	Hiyerarşik Kümeleme, hiyerarşik kümeleme, agglomerative clustering, hierarchical agglomerative clustering
関連	4	4
概要	Mean Shift is a non-parametric, iterative mode-seeking algorithm that identifies clusters as the peaks of an underlying probability density function. Originally introduced by Fukunaga and Hostetler (1975) for gradient estimation in pattern recognition, it was substantially extended and popularized by Comaniciu and Meer (2002) for robust feature-space analysis and image segmentation. Unlike k-means, Mean Shift requires no prior specification of the number of clusters, deriving cluster structure entirely from the data density.	Hierarchical clustering is an unsupervised method that groups observations into nested clusters and draws the result as a dendrogram, so the number of clusters need not be fixed in advance. Its agglomerative form rests on the objective-function grouping criterion introduced by Joe Ward in 1963.