Condorcet's Principle and the Preference Reversal Paradox
Abstract
We prove that every Condorcetconsistent voting rule can be manipulated by a voter who completely reverses their preference ranking, assuming that there are at least 4 alternatives. This corrects an error and improves a result of [Sanver, M. R. and Zwicker, W. S. (2009). Oneway monotonicity as a form of strategyproofness. Int J Game Theory 38(4), 553574.] For the case of precisely 4 alternatives, we exactly characterise the number of voters for which this impossibility result can be proven. We also show analogues of our result for irresolute voting rules. We then leverage our result to state a strong form of the GibbardSatterthwaite Theorem.
 Publication:

arXiv eprints
 Pub Date:
 July 2017
 arXiv:
 arXiv:1707.08760
 Bibcode:
 2017arXiv170708760P
 Keywords:

 Computer Science  Computer Science and Game Theory
 EPrint:
 In Proceedings TARK 2017, arXiv:1707.08250. 15 pages