preprints and working papers

2024

1. Axiomatic Characterizations of Draft Rules

   Jacob Coreno, and Ivan Balbuzanov

   Revision requested at the Journal of Economic Theory
   arXiv preprint arXiv:2204.08300, 2024

   Abs arXiv Slides

   Drafts are sequential allocation procedures for distributing heterogeneous and indivisible objects among agents subject to some priority order (e.g., allocating players’ contract rights to teams in professional sports leagues). Agents report ordinal preferences over objects and bundles are partially ordered by pairwise comparison. We provide a simple characterization of draft rules: they are the only allocation rules which are respectful of a priority (RP), envy-free up to one object (EF1), non-wasteful (NW) and resource monotonic (RM). RP and EF1 are crucial for competitive balance in sports leagues. We also prove three related impossibility theorems showing that the competitive-balance axioms RP and EF1 are generally incompatible with strategy-proofness. However, draft rules satisfy maxmin strategy-proofness. If agents may declare some objects unacceptable, then draft rules are characterized by RP, EF1, NW, and RM, in conjunction with individual rationality and truncation invariance. In a model with variable populations, draft rules are characterized by EF1, EFF, and RM, together with (population) consistency, top-object consistency, and neutrality.

2. Some Characterizations of TTC in Multiple-Object Reallocation Problems
   (Job Market Paper)

   Jacob Coreno, and Di Feng

   An extended abstract appeared in the proceedings of the 7th International Workshop on Matching Under Preferences (MATCH-UP 2024)
   arXiv preprint arXiv:2404.04822, 2024

   Abs arXiv Slides

   This paper considers exchange of indivisible objects when agents are endowed with and can consume any bundles. We focus on efficient allocation rules that satisfy a novel participation requirement, the weak endowment lower bound, and which defend against simple manipulation heuristics: drop strategies and truncation strategies. Based on these properties, we obtain characterizations of a generalized version of Top Trading Cycles (TTC) on several domains. On the lexicographic and conditionally lexicographic domains, TTC is characterized by Pareto efficiency, balancedness, the weak endowment lower bound, and truncation proofness (or drop strategy-proofness). On the domain of responsive preferences, similar characterizations are obtained by restricting attention to rules that are “individual-good-based” and weakening Pareto efficiency to individual-good efficiency. For the Shapley-Scarf model, TTC is characterized by Pareto efficiency, individual rationality, and truncationproofness. The lexicographic and conditionally lexicographic domains are maximal domains on which Pareto efficiency coincides with individual-good efficiency.

3. Justified Fairness in House Allocation Problems: Two Characterizations of Strategy-proof Mechanisms

   Di Feng, and Jacob Coreno

   arXiv preprint arXiv:2407.14101, 2024

   Abs arXiv

   We consider the house allocation problems with strict preferences, where monetary transfers are not allowed. We propose two properties in the spirit of justified fairness. Interestingly, together with other well-studied properties (strategy-proofness and non-bossiness), our two new properties identify serial dictatorships and sequential dictatorships, respectively.

4. Characterizing TTC via endowments-swapping-proofness and truncation-proofness

   Jacob Coreno, and Di Feng

   2024

   Abs PDF

   In the object reallocation problem introduced by Shapley and Scarf (1974), Fujinaka and Wakayama (2018) showed that Top Trading Cycles (TTC) is the unique rule satisfying individual rationality, strategy-proofness, and endowments-swapping-proofness. We show that the uniqueness remains true if strategy-proofness is weakened to truncation-proofness.