Author:
Schlotter Ildikó,Cechlárová Katarína,Trellová Diana
Abstract
AbstractConsider elections where the set of candidates is partitioned into parties, and each party must nominate exactly one candidate. The Possible President problem asks whether some candidate of a given party can become the unique winner of the election for some nominations from other parties. We perform a multivariate computational complexity analysis of Possible President for several classes of elections based on positional scoring rules. We consider the following parameters: the size of the largest party, the number of parties, the number of voters and the number of voter types. We provide a complete computational map of Possible President in the sense that for each choice of the four possible parameters as (i) constant, (ii) parameter, or (iii) unbounded, we classify the computational complexity of the resulting problem as either polynomial-time solvable or -complete, and for parameterized versions as either fixed-parameter tractable or [1]-hard with respect to the parameters considered.
Funder
Magyar Tudományos Akadémia
Agentúra na Podporu Výskumu a Vývoja
Vedecká Grantová Agentúra MŠVVaŠ SR a SAV
Faculty of Science, P.J. Šafárik University
HUN-REN Centre for Economic and Regional Studies
Publisher
Springer Science and Business Media LLC
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