Creative Commons Attribution 3.0 Unported license
When selecting locations for a set of centers, standard clustering algorithms may place unfair burden on some individuals and neighborhoods. We formulate a fairness concept that takes local population densities into account. In particular, given k centers to locate and a population of size n, we define the "neighborhood radius" of an individual i as the minimum radius of a ball centered at i that contains at least n/k individuals. Our objective is to ensure that each individual has a center that is within at most a small constant factor of her neighborhood radius. We present several theoretical results: We show that optimizing this factor is NP-hard; we give an approximation algorithm that guarantees a factor of at most 2 in all metric spaces; and we prove matching lower bounds in some metric spaces. We apply a variant of this algorithm to real-world address data, showing that it is quite different from standard clustering algorithms and outperforms them on our objective function and balances the load between centers more evenly.
@InProceedings{jung_et_al:LIPIcs.FORC.2020.5,
author = {Jung, Christopher and Kannan, Sampath and Lutz, Neil},
title = {{Service in Your Neighborhood: Fairness in Center Location}},
booktitle = {1st Symposium on Foundations of Responsible Computing (FORC 2020)},
pages = {5:1--5:15},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-142-9},
ISSN = {1868-8969},
year = {2020},
volume = {156},
editor = {Roth, Aaron},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.FORC.2020.5},
URN = {urn:nbn:de:0030-drops-120215},
doi = {10.4230/LIPIcs.FORC.2020.5},
annote = {Keywords: Fairness, Clustering, Facility Location}
}