Strategic voting
Strategic or tactical voting is voting in consideration of possible ballots cast by other voters in order to maximize one’s satisfaction with the election’s results. Gibbard’s theorem shows that no voting system has a single “always-best” strategy, i.e. one that always maximizes a voter’s satisfaction with the result, regardless of other voters’ ballots. This implies all voting systems can sometimes encourage voters to strategize. However, weaker guarantees can be shown under stronger conditions. Examples include one-dimensional preferences.
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