Consistency of scoring rules: A reinvestigation of composition-consistency
Öztürk,Emel
Öztürk,Emel
Abstract
We consider a collective choice problem in which the number of alternatives and the number of voters vary. Two fundamental axioms of consistency in such a setting, reinforcement and composition-consistency, are incompatible. We first observe that the latter implies four conditions each of which can be formulated as a consistency axiom on its own right. We find that two of these conditions are compatible with reinforcement. In fact, one of these, called composition-consistency with respect to non-clone winners, turns out to characterize a class of scoring rules which contains the Plurality rule. When combined with a requirement of monotonicity, composition-consistency with respect to non-clone winners uniquely characterizes the Plurality rule. A second implication of composition-consistency leads to a class of scoring rules that always select a Plurality winner when combined with monotonicity.
Description
Date
2020-09
Journal Title
Journal ISSN
Volume Title
Publisher
Research Projects
Organizational Units
Journal Issue
Keywords
plurality rule, cloning-consistency, composition-consistency, reinforcement, scoring rules, monotonicity, D70 - General, D71 - Social Choice ; Clubs ; Committees ; Associations, D72 - Political Processes: Rent-Seeking, Lobbying, Elections, Legislatures, and Voting Behavior
Citation
Öztürk, E 2020, 'Consistency of scoring rules : A reinvestigation of composition-consistency', International Journal of Game Theory, vol. 49, no. 3, pp. 801-831. https://doi.org/10.1007/s00182-020-00711-7
License
info:eu-repo/semantics/openAccess