I consider the problem of assigning agents to indivisible objects, in which each agent pays a price for his object and all prices sum to a given constant. The objective is to select an assignment-price pair that is envy-free with respect to the agents' true preferences. I propose a simple...

This paper studies the problem of assigning a set of indivisible objects to a set of agents when monetary transfers are not allowed and agents reveal only ordinal preferences, but random assignments are possible. We offer two characterizations of the probabilistic serial mechanism, which assigns...

We revisit the classical object reallocation problem under strict preferences. When attention is constrained to the set of Pareto-efficient rules, it is known that TTC is the only rule that is strategyproof and individually-rational. We hence relax this constraint and consider pair-efficiency. A...

We search for impartiality in the allocation of objects when monetary transfers are not possible. Our main focus is anonymity. The standard definition requires that if agents' names are permuted, their assignments should be permuted in the same way. Since no rule satisfies this definition in...

In this paper we are interested in efficient and individually rational exchange rules for markets with heterogeneous indivisible goods that exclude the possibility that an agent benefits by regrouping goods in her initial endowment. We present a suitable environment in which the existence of...

The ex ante incentive compatible core of an exchange economy with private information is the (standard) core of a socially designed characteristic function, which expresses the fact that coalitions allocate goods by means of random incentive compatible mechanisms. We first survey some results in...

We consider house allocation problems (Shapley and Scarf, 1974) with strict preferences. We introduce a new axiom called pre-exchange-proofness, which states that no pair of agents gain by exchanging their endowments with each other prior to the operation of the chosen rule. We establish that a...

We consider house (re)allocation problems (Shapley and Scarf, 1974) with strict preferences. We are concerned with the possibility that a pair of agents may gain by swapping their endowments before the operation of the chosen rule. A rule is called endowments-swapping-proof if it is immune to...

Each of n ≥ 1 identical buyers (and m ≥ 1 identical sellers) wants to buy (sell) a single unit of an indivisible good. The core predicts a unique and extreme outcome: the entire surplus is split evenly among the buyers when m n and among the sellers when m n; the long side gets nothing. We...

The allocation and exchange of discrete resources, such as transplant organs, pub- lic housing, dormitory rooms, and many other resources for which agents have single-unit demand, is often conducted via direct mechanisms without monetary transfers. Incentive compatibility and ef?ciency are...