The Solid Coalition Refinement Rule: Tractability and Extensions

Speaker(s)

Grzegorz Kwacz

Affiliation

University of Warsaw

Language of the talk

English

Date

May 28, 2026, 12:30 p.m.

Room

room 4060

Seminar

Seminar Algorithmic Economics

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The Solid Coalition Refinement rule was recently proposed for ranked voting setting. It main goal was to guarantee proportionality and satisfy committee monotonicity. We study the computational complexity of the rule, proposing fixed parameter tractable algorithms for the main parameters. We also extend the rule and provide proportionality guarantees to the matroid constrains, which generalize the many other settings, including public decisions and committee elections with attributes or negative votes. Lastly, we conduct experiments, comparing the rule to other popular ranked voting rules, including Single Transferable Vote and Expanding Approvals Rule.

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