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arXiv · 2207.00966

An Empirical Evaluation of $k$-Means Coresets

Abstract

Coresets are among the most popular paradigms for summarizing data. In particular, there exist many high performance coresets for clustering problems such as $k$-means in both theory and practice. Curiously, there exists no work on comparing the quality of available $k$-means coresets. In this paper we perform such an evaluation. There currently is no algorithm known to measure the distortion of a candidate coreset. We provide some evidence as to why this might be computationally difficult. To complement this, we propose a benchmark for which we argue that computing coresets is challenging and which also allows us an easy (heuristic) evaluation of coresets. Using this benchmark and real-world data sets, we conduct an exhaustive evaluation of the most commonly used coreset algorithms from theory and practice.

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BibTeXRIS

Chris Schwiegelshohn, Omar Ali Sheikh-Omar. 2022-07-03. An Empirical Evaluation of $k$-Means Coresets. https://arxiv.org/abs/2207.00966

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