The consumption of an indivisible good causes identity-dependent externalities to non-consumers. We analyse resale markets where the current owner designs the trading procedure, but cannot commit to future actions. We ask the following questions: (1) Does the identity of the initial owner matter for the determination of the final consumer? (2) Is the outcome always efficient? The major conclusion of our paper is that the irrelevance of the initial structure of property rights arises in resale processes even if there are transaction costs that hinder efficiency. This result complements the Coasian view where the irrelevance of the assignment of property rights is a consequence of efficiency.

We study efficient, Bayes-Nash incentive compatible mechanisms in a social choice setting that allows for informational and allocative externalities. We show that such mechanisms exist only if a congruence condition relating private and social rates of information substitution is satisfied. If signals are multi-dimensional, the congruence condition is determined by an integrability constraint, and it can hold only in nongeneric cases where values are private or a certain symmetry assumption holds. If signals are one-dimensional, the congruence condition reduces to a monotonicity constraint and it can be generically satisfied. We apply the results to the study of multi-object auctions, and we discuss why such auctions cannot be reduced to one-dimensional models without loss of generality.

We study the strategic equilibria of a negotiation game where potential buyers are affected by identity-dependent, negative externalities. The unique equilibrium of long, finitely repeated generic games can either display delay--where a transaction can take place only in several stages before the deadline--or, in spite of the random element in the game, a well-defined buyer exists that obtains the object with probability close to one.

In 1797 Johann Wolfgang von Goethe sold a manuscript through a second‐price auction. We investigate Goethe's motivation in the context of the late eighteenth century's book market and relate it to modern auction theory.

We analyze sequential, binary voting schemes in settings where several privately informed agents have single-peaked preferences over a finite set of alternatives, and we focus on robust equilibria that do not depend on assumptions about the players' beliefs about each other. Our main results identify two intuitive conditions on binary voting trees, ensuring that sincere voting at each stage forms an ex post perfect equilibrium. In particular, we uncover a strong rationale for content-based agendas: if the outcome should not be sensitive to beliefs about others, nor to the deployment of strategic skills, the agenda needs to be built “from the extremes to the middle” so that more extreme alternatives are both more difficult to adopt, and are put to vote before other, more moderate options. An important corollary is that, under simple majority, the equilibrium outcome of the incomplete information game is always the Condorcet winner. Finally, we aim to guide the practical design of schemes that are widely used by legislatures and committees and we illustrate our findings with several case studies.

We study an allocation problem where a set of objects needs to be allocated to agents arriving over time. The basic model is of the private, independent values type. The dynamically efficient allocation is implementable if the distribution of agents' values is known. Whereas lack of knowledge about the distribution is inconsequential in the static case, endogenous informational externalities arise if the designer gradually learns about the distribution by observing present values. These externalities may prevent the implementation of the dynamically efficient allocation. We provide necessary and sufficient conditions for the efficient allocation to be implementable.

We study a contest with multiple, nonidentical prizes. Participants are privately informed about a parameter (ability) affecting their costs of effort. The contestant with the highest effort wins the first prize, the contestant with the second-highest effort wins the second prize, and so on until all the prizes are allocated. The contest's designer maximizes expected effort. When cost functions are linear or concave in effort, it is optimal to allocate the entire prize sum to a single “first” prize. When cost functions are convex, several positive prizes may be optimal.

We study the problem of a seller who wants to maximize her revenue in situations where the outcome of the sale affects the nature of the future interaction between agents. We model those situations by assuming that an agent that does not acquire the object for sale incurs an externality that may depend both on the identity of the sufferer and on the identity of the final purchaser. We describe an optimal auction that has a unique Nash equilibrium in strictly dominant strategies. We show that: 1) Outside options are endogenously determined in equilibrium. Participation constraints and the ''threats'' in case of non-participation play an important role. 2) An optimizing seller can extract surplus also from buyers that do not obtain the auctioned object. 3) The seller is better off by not selling at all (while obtaining some payments) if externalities are large when compared to the pure profits that buyers achieve if they acquire the object. 4) The revenue-maximizing equilibrium is coalition-proof if buyers cannot organize side payments among themselves. (orig.)

We study auction design for bidders equipped with non-expected utility preferences that exhibit constant risk aversion (CRA). The CRA class is large and includes loss-averse, disappointment-averse, mean-dispersion, and Yaari’s dual preferences as well as coherent and convex risk measures. Any preference in this class displays first-order risk aversion, contrasting the standard expected utility case which displays second-order risk aversion. The optimal mechanism offers “ full-insurance” in the sense that each agent’s utility is independent of other agents’ reports. The seller excludes less types than under risk neutrality and awards the object randomly to intermediate types. Subjecting intermediate types to a risky allocation while compensating them when losing allows the seller to collect larger payments from higher types. Relatively high types are willing to pay more, and their allocation is efficient.

We use the tools of mechanism design combined with the theory of risk measures to analyze how a cash-constrained owner of an asset with known, stochastic returns raises capital from a population of investors who differ in their risk aversion and budget constraints. The issuer partitions the asset’s cash flow into several asset-backed securities, one for each type of investor. The optimal partition conforms to the commonly observed practice of tranching into senior debt, junior debt, and equity. Tranching arises endogenously due to the differences in risk appetites among agents and in the budget constraints they face.