Aggregating sets of von Neumann-Morgenstern utilities

Printer-friendly version
Working paper
Author/s: 
Eric Danan, Thibault Gajdos and Jean-Marc Tallon
Issue number: 
2010.68
Publisher: 
Centre d’Economie de la Sorbonne
Year: 
2010
We analyze the aggregation problem without the assumption that individuals and society have fully determined and observable preferences. More precisely, we endow individuals and society with sets of possible von Neumann-Morgenstern utility functions over lotteries. We generalize the classical neutrality assumption to this setting and characterize the class of neutral social welfare function. This class turns out to be considerably broader for indeterminate than for determinate utilities, where it basically reduces to utilitarianism. In particular, aggregation rules may differ by the relationship between individual and social indeterminacy. We characterize several subclasses of neutral aggregation rules and show that utilitarian rules are those that yield the least indeterminate social utilities, although they still fail to systematically yield a determinate social utility.
Developed by Paolo Gittoi