Schulze STV

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Schulze STV is a draft single transferable vote (STV) ranked voting system designed to achieve proportional representation.^[1][2] It was invented by Markus Schulze, who developed the Schulze method for resolving ties using a Condorcet method. Schulze STV is similar to CPO-STV in that it compares possible winning candidate pairs and selects the Condorcet winner. It is not used in parliamentary elections.

The system is based on Schulze's investigations into vote management and free riding.^[3] When a voter prefers a popular candidate, there is an advantage to first choosing a candidate who is unlikely to win (Woodall free riding) or omitting his preferred candidate from his rankings (Hylland free riding).

Schulze STV is designed to be as resistant to free riding as possible, without giving up the Droop proportionality criterion.^[1]