Fair group decisions via non-deterministic proportional consensus

Bibliographic Data

ID21470450
AuthorsJ Heitzig (0000-0002-0442-8077, Potsdam Institute for Climate Impact Research, corresponding author), Forest W Simmons (Portland Community College), Sara M Constantino (0000-0001-5533-5885, Northeastern University)
Year2025
Volume64
Issue1-2
Pages345-371
Publication date2025-02-01
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueSocial Choice and Welfare (JOURNAL)
Journal identifiersISSN: 0176-1714 • E-ISSN: 1432-217X
PublisherSpringer Science and Business Media LLC (PUBLISHER)
DOI10.1007/s00355-024-01524-3
OpenAlexW4396642114
LanguageFR
Citations received1
References cited44

Are there group decision methods which (i) give everyone, including minorities, an equal share of effective decision power even when voters act strategically, (ii) promote consensus and equality, rather than polarization and inequality, and (iii) do not favour the status quo or rely too much on chance? We describe two non-deterministic group decision methods that meet these criteria, one based on automatic bargaining over lotteries, the other on conditional commitments to approve compromise options. Using theoretical analysis, agent-based simulations and a behavioral experiment, we show that these methods prevent majorities from consistently suppressing minorities, which can happen in deterministic methods, and keeps proponents of the status quo from blocking decisions, as in other consensus-based approaches. Our simulations show that these methods achieve aggregate welfare comparable to common voting methods, while employing chance judiciously, and that the welfare costs of fairness and consensus are small compared to the inequality costs of majoritarianism. In an incentivized experiment with naive participants, we find that a sizable fraction of participants prefers to use a non-deterministic voting method over Plurality Voting to allocate monetary resources. However, this depends critically on their position within the group. Those in the majority show a strong preference for majoritarian voting methods

Econometrics · Economics · International political economy · Macroeconomics · Mathematical economics · Physics · Political science · Public finance · Social policy · Experimental Behavioral Economics Studies · Game Theory and Applications · Game Theory and Voting Systems · Law · Mathematics

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