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arXiv · 2309.07486

Massively-Parallel Heat Map Sorting and Applications To Explainable Clustering

Sepideh Aghamolaei·Mohammad Ghodsi
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Abstract

Given a set of points labeled with $k$ labels, we introduce the heat map sorting problem as reordering and merging the points and dimensions while preserving the clusters (labels). A cluster is preserved if it remains connected, i.e., if it is not split into several clusters and no two clusters are merged. We prove the problem is NP-hard and we give a fixed-parameter algorithm with a constant number of rounds in the massively parallel computation model, where each machine has a sublinear memory and the total memory of the machines is linear. We give an approximation algorithm for a NP-hard special case of the problem. We empirically compare our algorithm with k-means and density-based clustering (DBSCAN) using a dimensionality reduction via locality-sensitive hashing on several directed and undirected graphs of email and computer networks.

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Sepideh Aghamolaei, Mohammad Ghodsi. 2023-09-14. Massively-Parallel Heat Map Sorting and Applications To Explainable Clustering. https://arxiv.org/abs/2309.07486

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