Let 𝝫𝑛 be the set of the binary strategy-proof social choice functions referred to a group of n voters who are allowed to declare indifference between the alternatives. We provide a recursive way to obtain the set 𝝫𝑛+1 from the set 𝝫𝑛. Computing the cardinalities |𝝫𝑛|...

We analyze bankruptcy problems with an indivisible object, where real owners and outside traders want to allocate an indivisible object among them with monetary compensation. The object might be a company that has gone bankrupt or a house left by a parent who has died, and so on. We show that...

In this paper, we show that in pure exchange economies where the number of goods equals or exceeds the number of agents, any Pareto-efficient and strategy-proof allocation mechanism always allocates the total endowment to some single agent even if the receivers vary.

In a voting model where the set of feasible alternatives is a subset of a product set $A = A_1\times\cdots\ldots{}A_m$ of $m$ finite categories, we characterize the set of all strategy-proof social choice functions for three different types of preference domains over $A$, namely for the domains...

We study strategy-proof rules for choosing between two alternatives. We consider the full preference domain which allows for indifference. In this framework, for strategy proof rules, ontoness does not imply efficiency. We weaken the requirement of efficiency to ontoness and characterizes the...

Condorcet domains are sets of linear orders with the property that, whenever the preferences of all voters of a society belong to this set, their majority relation has no cycles. We observe that, without loss of generality, every such domain can be assumed to be closed in the sense that it...

This paper considers the problem of allocating N indivisible objects among N agents according to their preferences when transfers are not allowed, and studies the tradeoff between fairness and efficiency in the class of strategy-proof mechanisms. The main finding is that for strategy-proof...

This paper generalizes the results in Aswal et al. (2003) on dictatorial domains. This is done in two ways. In the first, the notion of connections between pairs of alternatives in Aswal et al. (2003) is weakened to weak connectedness. This notion requires the specification of four preference...

In this paper we consider the exogenous indifference classes model of Barberá and Ehlers (2011) and Sato (2009) and analyze further the relationship between the structure of indifference classes across agents and dictatorship results. The key to our approach is the pairwise partition graph. We...

Consider a setting in which individual strict preferences need to be aggregated into a social strict preference relation. For two alternatives and an odd number of agents, it follows from May’s Theorem that the majority aggregation rule is the only one satisfying anonymity, neutrality, and...