,
Nils Morawietz
,
Jesse van Rhijn
,
Frank Sommer
Creative Commons Attribution 4.0 International license
We show that the simplest local search heuristics for two natural Euclidean clustering problems are PLS-hard. First, we show that the Hartigan-Wong method, which is essentially the Flip heuristic, for k-Means clustering is PLS-hard, even when k = 2. Second, we show the same result for the Flip heuristic for Max Cut, even when the edge weights are given by the (squared) Euclidean distances between the points in some set 𝒳 ⊆ R^d; a problem which is equivalent to Min Sum 2-Clustering.
@InProceedings{manthey_et_al:LIPIcs.ISAAC.2024.48,
author = {Manthey, Bodo and Morawietz, Nils and van Rhijn, Jesse and Sommer, Frank},
title = {{Complexity of Local Search for Euclidean Clustering Problems}},
booktitle = {35th International Symposium on Algorithms and Computation (ISAAC 2024)},
pages = {48:1--48:16},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-354-6},
ISSN = {1868-8969},
year = {2024},
volume = {322},
editor = {Mestre, Juli\'{a}n and Wirth, Anthony},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ISAAC.2024.48},
URN = {urn:nbn:de:0030-drops-221755},
doi = {10.4230/LIPIcs.ISAAC.2024.48},
annote = {Keywords: Local search, PLS-complete, max cut, k-means, partitioning problem, flip-neighborhood}
}