We study preference aggregation under uncertainty when individual and collective preferences are based on subjective expected utility  . A natural procedure for determining the collective preferences of a group then is to average its members' beliefs and add up their (0,1)-normalized utility functions . This procedure extends the well-known relative utilitarianism to decision making under uncertainty. We show that it is the only aggregation function that gives tie-breaking rights to agents who join a group and satisfies an independence condition in the spirit of Arrow's independence of irrelevant alternatives as well as four undiscriminating axioms .
How should a group of agents decide among actions whose consequences are uncertain? I study this problem when agents and groups are subjective expected utility maximizers . A natural way to determine the preferences of a group then is relative utilitarianism with belief averaging: add up the agents' (0,1)-normalized utility functions and average their beliefs. I show that it is the only way to aggregate preferences that is monotonic in the agents' preferences and ignores preferences over redundant actions. The monotonicity condition ensures that an agent who joins a group gets to break ties in her favor if differences in preferences are due solely to differences in the utility functions .
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We study preference aggregation under uncertainty when individual and collective preferences are based on
How should a group of agents decide among actions whose consequences are uncertain? I study this problem when agents and groups are
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maximizers
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procedure for determining the collective
way to determine the
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to average its members' beliefs and add up their
relative utilitarianism with belief averaging: add up the agents'
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. This procedure extends the well-known relative utilitarianism to decision making under uncertainty. We
and average their beliefs. I
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aggregation function that gives tie-breaking rights to agents who join a group and satisfies an independence condition in the spirit of Arrow's independence of irrelevant alternatives as well as four undiscriminating axioms
way to aggregate preferences that is monotonic in the agents' preferences and ignores preferences over redundant actions. The monotonicity condition ensures that an agent who joins a group gets to break ties in her favor if differences in preferences are due solely to differences in the utility functions