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arXiv · 1608.07494

Estimating the Number of Clusters via Normalized Cluster Instability

Jonas M. B. Haslbeck·Dirk U. Wulff
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Abstract

We improve current instability-based methods for the selection of the number of clusters $k$ in cluster analysis by developing a normalized cluster instability measure that corrects for the distribution of cluster sizes, a previously unaccounted driver of cluster instability. We show that our normalized instability measure outperforms current instability-based measures across the whole sequence of possible $k$ and especially overcomes limitations in the context of large $k$. We also compare, for the first time, model-based and model-free approaches to determine cluster-instability and find their performance to be comparable. We make our method available in the R-package \verb+cstab+.

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Jonas M. B. Haslbeck, Dirk U. Wulff. 2016-08-26. Estimating the Number of Clusters via Normalized Cluster Instability. https://arxiv.org/abs/1608.07494

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