Declared strategy voting

Declared strategy voting or DSV is a type of election method that works by submitting strategic votes to an underlying election method. The name was first used in 1995 by L. F. Cranor.

By voting in a DSV method, the voter provides the method with an instruction of whom to optimize the ballot for. For instance, if the DSV method is given a ranked ballot that ranks A first and B second, that means that the method should try to optimize that voter's ballot so as to elect A, and in the cases where it's impossible to get A elected, to optimize in favor of B.

The purpose of a DSV method is to resist voter strategy and thus level the playing field between honest and strategic voters. Because of Gibbard's theorem, it is never possible to completely do so; but DSV methods tend to be more resistant to strategy than the methods they're based on.

Unfortunately, DSV methods also tend to fail criteria that the underlying methods pass. For instance, most forms of Plurality DSV fail monotonicity, even though Plurality itself passes it.