Multiperson Utility

We approach the problem of preference aggregation by endowing both individuals and coalitions with partially-ordered or incomplete cardinal preferences. Consistency across preferences for coalitions comes in the form of the Extended Pareto Rule: if two disjoint coalitions A and B prefer x to y, then so does the coalition A*B. The Extended Pareto Rule has important consequences for the social aggregation of individual preferences. Restricting attention to the case of complete individual preferences, and assuming complete preferences for some pairs of agents (interpersonal comparisons of utility units), we discover that the Extended Pareto Rule imposes a "no arbitrage" condition in the terms of utility comparison between agents. Furthermore, if all the individuals and pairs have complete preferences and certain non-degeneracy conditions are met, then we witness the emergence of a complete preference ordering for coalitions of all sizes. The corresponding utilities are a weighted sum of individual utilities, with the n-1 independent weights obtained from the preferences of n-1 pairs forming a spanning tree in the group. Keywords: Preference aggregation, Incomplete preferences, Extended Pareto Rule.

Marshallian Money, Welfare, and Side-Payments

A link between a no-side-payment (NSP) market game and a side-payment (SP) market game can be established by introducing a sufficient amount of an ideal utility-money of constant marginal utility to all agents. At some point when there is "enough money" in the system, if it is "well distributed" the new game will be a SP game. This game can also be related to a pure NSP game where a set of default parameters have been introduced. These parameters play a role similar to the parameters specifying the interpersonal comparisons in the side-payment game. We study this game for the properties of the delta-core and consider both the conditions for the uniqueness of competitive equilibria and a new approach to the second welfare theorem. A discussion of the relationship between market games and strategic market games is also noted.delta-core, enough money, market games