Let's Agree to Agree: Targeting Consensus for Incomplete Preferences through Majority Dynamics
This addresses decision-making challenges for groups with incomplete preferences, but it is incremental as it builds on existing consensus notions and majority dynamics.
The paper tackles the problem of collective decision-making among agents with incomplete preferences using majority dynamics, showing that while myopic adherence to the majority can damage consensus like the Condorcet winner in worst-case scenarios, simulation experiments indicate this damage is often mild.
We study settings in which agents with incomplete preferences need to make a collective decision. We focus on a process of majority dynamics where issues are addressed one at a time and undecided agents follow the opinion of the majority. We assess the effects of this process on various consensus notions -- such as the Condorcet winner -- and show that in the worst case, myopic adherence to the majority damages existing consensus; yet, simulation experiments indicate that the damage is often mild. We also examine scenarios where the chair of the decision process can control the existence (or the identity) of consensus, by determining the order in which the issues are discussed.