Spectral clustering: Difference between revisions

Revision as of 13:41, 28 June 2012

Revision as of 13:43, 28 June 2012

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This partitioning may be done in various ways, such as by taking the median <math>m</math> of the components in <math>v</math>, and placing all points whose component in <math>v</math> is greater than <math>m</math> in <math>B_1</math>, and the rest in <math>B_2</math>. The algorithm can be used for hierarchical clustering by repeatedly partitioning the subsets in this fashion.

A related algorithm is the '''[[Meila–Shi algorithm]]'''<ref>Marina Meilă & Jianbo Shi, "[http://www.citeulike.org/user/mpotamias/article/498897 Learning Segmentation by Random Walks]", Neural Information Processing Systems 13 (NIPS 2000), 2001, pp. 873–879.</ref>, which takes the [[eigenvector]]s corresponding to the ''k'' largest [[eigenvalue]]s of the matrix <math>P = SD^{-1}</math> for some ''k'', and then invokes another algorithm (e.g. ''[[k''-means clustering]]) to cluster points by their respective ''k'' components in these eigenvectors.

== Relationship with ''k''-means ==