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arXiv · 1509.04595

Are there any nicely structured preference~profiles~nearby?

Robert Bredereck·Jiehua Chen·Gerhard J. Woeginger
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Abstract

We investigate the problem of deciding whether a given preference profile is close to having a certain nice structure, as for instance single-peaked, single-caved, single-crossing, value-restricted, best-restricted, worst-restricted, medium-restricted, or group-separable profiles. We measure this distance by the number of voters or alternatives that have to be deleted to make the profile a nicely structured one. Our results classify the problem variants with respect to their computational complexity, and draw a clear line between computationally tractable (polynomial-time solvable) and computationally intractable (NP-hard) questions.

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Robert Bredereck, Jiehua Chen, Gerhard J. Woeginger. 2015-09-15. Are there any nicely structured preference~profiles~nearby?. https://arxiv.org/abs/1509.04595

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