A distance-based aggregation method for finding consensus in preference-approvals

Albano, Alessandro;Romano, Maurizio

2026-01-01

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Abstract

This paper proposes a distance-based aggregation and consensus method for preference-approvals with potential applications in group decision-making, recommendation systems, and social choice theory. Preference-approvals are a type of preference data where individuals provide a list of approved alternatives in addition to a strict ranking. The proposed method aims to synthesise individual preference-approvals into a unified consensus representing the group’s collective view. The consensus is the preference-approval, which minimises the average distance within the whole set of voters. The performance of the proposed method is investigated through a sensitivity analysis on the weighting parameter, two simulation studies, and two real-data applications.