Abstract
It is important to study how strategic agents can affect the outcome of an election. There has been a long line of research in the computational study of elections on the complexity of manipulative actions such as manipulation and bribery. These problems model scenarios such as voters casting strategic votes and agents campaigning for voters to change their votes to make a desired candidate win. A common assumption is that the preferences of the voters follow the structure of a domain restriction such as single peakedness, and so manipulators only consider votes that also satisfy this restriction. We introduce the model where the preferences of the voters define their own restriction and strategic actions must “conform” by using only these votes. In this model, the election after manipulation will retain common domain restrictions. We explore the computational complexity of conformant manipulative actions and we discuss how conformant manipulative actions relate to other manipulative actions.
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Notes
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We will see that this rule exhibits very unusual complexity behavior. This rule has also been referred to as “best-worst” in social choice (see, e.g., [24]).
- 2.
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Acknowledgements
This work was supported in part by grant NSF-DUE-1819546. We thank the anonymous reviewers for their helpful comments and suggestions.
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Fitzsimmons, Z., Hemaspaandra, E. (2023). Complexity of Conformant Election Manipulation. In: Fernau, H., Jansen, K. (eds) Fundamentals of Computation Theory. FCT 2023. Lecture Notes in Computer Science, vol 14292. Springer, Cham. https://doi.org/10.1007/978-3-031-43587-4_13
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