The Complexity of Nearly Single-Peaked Consistency1
نویسندگان
چکیده
Manipulation, bribery, and control are well-studied ways of changing the outcome of an election. Many voting systems are in the general case computationally resistant to some of these manipulative actions. However when restricted to single-peaked electorates, these problems suddenly become easy to solve. Recently, Faliszewski, Hemaspaandra, and Hemaspaandra [FHH11] studied the complexity of dishonest behavior in nearly single-peaked electorates. These are electorates that are not single-peaked but close to it according to some distance measure. In this paper we introduce several new distance measures regarding single-peakedness. We prove that determining whether a given profile is nearly single-peaked is in many cases NPcomplete. Furthermore, we explore the relations between several notions of nearly singlepeakedness.
منابع مشابه
Computational Aspects of Nearly Single-Peaked Electorates
Manipulation, bribery, and control are well-studied ways of changing the outcome of an election. Many voting systems are, in the general case, computationally resistant to some of these manipulative actions. However when restricted to single-peaked electorates, these systems suddenly become easy to manipulate. Recently, Faliszewski, Hemaspaandra, and Hemaspaandra (2011b) studied the complexity ...
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