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arXiv · 2507.06212

$k$-means considered harmful: On arbitrary topological changes in Mapper complexes

Mikael Vejdemo-Johansson
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Abstract

The Mapper construction is one of the most widespread tools from Topological Data Analysis. There is an unfortunate trend as the construction has gained traction to use clustering methods with properties that end up distorting any analysis results from the construction. In this paper we will see a few ways in which widespread choices of clustering algorithms have arbitrarily large distortions of the features visible in the final Mapper complex.

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Mikael Vejdemo-Johansson. 2025-07-08. $k$-means considered harmful: On arbitrary topological changes in Mapper complexes. https://arxiv.org/abs/2507.06212

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