Multimode Control Attacks on Elections

Piotr Faliszewski; Edith Hemaspaandra; Lane A. Hemaspaandra

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arXiv · 1007.1800

Multimode Control Attacks on Elections

Piotr Faliszewski·Edith Hemaspaandra·Lane A. Hemaspaandra

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Abstract

In 1992, Bartholdi, Tovey, and Trick opened the study of control attacks on elections---attempts to improve the election outcome by such actions as adding/deleting candidates or voters. That work has led to many results on how algorithms can be used to find attacks on elections and how complexity-theoretic hardness results can be used as shields against attacks. However, all the work in this line has assumed that the attacker employs just a single type of attack. In this paper, we model and study the case in which the attacker launches a multipronged (i.e., multimode) attack. We do so to more realistically capture the richness of real-life settings. For example, an attacker might simultaneously try to suppress some voters, attract new voters into the election, and introduce a spoiler candidate. Our model provides a unified framework for such varied attacks, and by constructing polynomial-time multiprong attack algorithms we prove that for various election systems even such concerted, flexible attacks can be perfectly planned in deterministic polynomial time.

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BibTeX RIS

Piotr Faliszewski, Edith Hemaspaandra, Lane A. Hemaspaandra. 2010-07-11. Multimode Control Attacks on Elections. https://arxiv.org/abs/1007.1800

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