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Title: Quickly Determining Who Won an Election
This paper considers elections in which voters choose one candidate each, independently according to known probability distributions. A candidate receiving a strict majority (absolute or relative, depending on the version) wins. After the voters have made their choices, each vote can be inspected to determine which candidate received that vote. The time (or cost) to inspect each of the votes is known in advance. The task is to (possibly adaptively) determine the order in which to inspect the votes, so as to minimize the expected time to determine which candidate has won the election. We design polynomial-time constant-factor approximation algorithms for both the absolute-majority and the relative-majority version. Both algorithms are based on a two-phase approach. In the first phase, the algorithms reduce the number of relevant candidates to O(1), and in the second phase they utilize techniques from the literature on stochastic function evaluation to handle the remaining candidates. In the case of absolute majority, we show that the same can be achieved with only two rounds of adaptivity.  more » « less
Award ID(s):
1909335
PAR ID:
10556875
Author(s) / Creator(s):
; ;
Editor(s):
Guruswami, Venkatesan
Publisher / Repository:
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Date Published:
Volume:
287
ISSN:
1868-8969
ISBN:
978-3-95977-309-6
Subject(s) / Keyword(s):
stochastic function evaluation voting approximation algorithms Theory of computation → Approximation algorithms analysis
Format(s):
Medium: X Size: 14 pages; 684346 bytes Other: application/pdf
Size(s):
14 pages 684346 bytes
Right(s):
Creative Commons Attribution 4.0 International license; info:eu-repo/semantics/openAccess
Sponsoring Org:
National Science Foundation
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