Tactical voting: Difference between revisions
Added pairwise-only Condorcet strategic susceptibility result.
(Added pairwise-only Condorcet strategic susceptibility result.) |
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=== Predisposition to sincerity ===
Some experiments have found that voters tend to behave sincerely more often than the instrumentally rational model indicates. In an experiment designed to have a low barrier to sophisticated voting, Herzberg and Wilson found that only 20%-40% of the voters made use of the opportunity; the rest voted sincerely.<ref name="Herzberg Wilson 1988 pp. 471–486">{{cite journal | last=Herzberg | first=Roberta Q. | last2=Wilson | first2=Rick K. | title=Results on Sophisticated Voting in an Experimental Setting | journal=The Journal of Politics | publisher=
Blais and Nadeau use a two-step analysis procedure to argue that 30% of the voters who would have benefited from strategic voting in the 1988 Canadian election actually did vote strategically.<ref name="Blais Nadeau 1996 pp. 39–52">{{cite journal | last=Blais | first=André | last2=Nadeau | first2=Richard | title=Measuring strategic voting: A two-step procedure | journal=Electoral Studies | publisher=Elsevier BV | volume=15 | issue=1 | year=1996 | issn=0261-3794 | doi=10.1016/0261-3794(94)00014-x | pages=39–52}}</ref> They furthermore reason that tactical voting is more prevalent if the voters have only a weak intensity of preference for their first choice over their second, or if the election is a close race between their second and third choice.
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Due to the especially deep impact of tactical voting in [[first past the post]] electoral systems, some argue that systems with three or more strong or persistent parties become in effect forms of [[disapproval voting]], where the expression of disapproval, to keep an opponent out of office overwhelms the expression of approval, to approve a desirable candidate. [[Ralph Nader]] refers to this as the "least worst" choice, and argues that the similarity of parties and the candidates grows stronger due to the need to avoid this disapproval.
Sirin Botan et al. showed that every Condorcet method of a particular type sometimes incentivizes the creation of Condorcet cycles when there's a sincere [[Condorcet winner]]. The types covered are Condorcet methods that only use pairwise defeat information and don't always tie when there's no Condorcet winner. <ref name="Botan Endriss 2021 pp. 5202–5210">{{cite journal | last=Botan | first=Sirin | last2=Endriss | first2=Ulle | title=Preserving Condorcet Winners under Strategic Manipulation | journal=Proceedings of the AAAI Conference on Artificial Intelligence | publisher=Association for the Advancement of Artificial Intelligence (AAAI) | volume=35 | issue=6 | date=2021-05-18 | issn=2374-3468 | doi=10.1609/aaai.v35i6.16657 | pages=5202–5210}}</ref>
There are arguments about the best voting strategy to take in different systems, but the general consensus is:
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