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arXiv · 2107.04074

Accelerating Spherical k-Means

Erich Schubert·Andreas Lang·Gloria Feher
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Abstract

Spherical k-means is a widely used clustering algorithm for sparse and high-dimensional data such as document vectors. While several improvements and accelerations have been introduced for the original k-means algorithm, not all easily translate to the spherical variant: Many acceleration techniques, such as the algorithms of Elkan and Hamerly, rely on the triangle inequality of Euclidean distances. However, spherical k-means uses Cosine similarities instead of distances for computational efficiency. In this paper, we incorporate the Elkan and Hamerly accelerations to the spherical k-means algorithm working directly with the Cosines instead of Euclidean distances to obtain a substantial speedup and evaluate these spherical accelerations on real data.

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Erich Schubert, Andreas Lang, Gloria Feher. 2021-07-08. Accelerating Spherical k-Means. https://doi.org/10.1007/978-3-030-89657-7_17

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