1. The complexity of manipulative attacks in nearly single-peaked electorates.
- Author
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Faliszewski, Piotr, Hemaspaandra, Edith, and Hemaspaandra, Lane A.
- Subjects
- *
COMPUTATIONAL complexity , *POLYNOMIAL time algorithms , *COMPUTER systems , *COMPUTER science , *ELECTRONIC data processing , *MACHINE theory - Abstract
Abstract: Many electoral control and manipulation problems—which we will refer to in general as “manipulative actions” problems—are NP-hard in the general case. It has recently been noted that many of these problems fall into polynomial time if the electorate is single-peaked, i.e., is polarized along some axis/issue. However, real-world electorates are not truly single-peaked. There are usually some mavericks, and so real-world electorates tend merely to be nearly single-peaked. This paper studies the complexity of manipulative-action algorithms for elections over nearly single-peaked electorates. We do this for many notions of nearness and for a broad range of election systems. We provide instances where even one maverick jumps the manipulative-action complexity up to NP-hardness, but we also provide many instances where some number of mavericks can be tolerated without increasing the manipulative-action complexity. [Copyright &y& Elsevier]
- Published
- 2014
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