Voting with evaluations: When should we sum? What should we sum?

Printer-friendly version
Working paper
Antonin Macé
Issue number: 
WP 2015 - Nr 44
AMSE Working Papers
Aix-Marseilles School of Economics
Most studies of the voting literature take place in the arrovian framework, in which voters rank the available alternatives, and where Arrow's impossibility theorem prevails. I consider a different informational basis for social decisions, by allowing individuals to evaluate alternatives rather than to rank them. Voters express their opinion by assigning to each alternative an evaluation from a given set. I focus on additive rules, which follow the utilitarian paradigm. If the evaluations are numbers, the elected alternative is the one with the highest sum of evaluations. I generalize this notion to any set of evaluations, taking into account the possibility of qualitative ones. I provide an axiomatization for each of the two main additive rules: "Range Voting" when the set of evaluations is [0, 1] and "Evaluative Voting" when the set of evaluations is finite.
Developed by Paolo Gittoi