arXiv subjects

Juan S. Pereyra

Publications and source records attributed to Juan S. Pereyra.

4 recordsLinked to original sources

arXiv2026

Time-constrained Dynamic Mechanisms for College Admissions

Recent literature shows that dynamic matching mechanisms may outperform their static counterparts. The college admissions procedure used in Inner Mongolia motivates an underexplored design dimension of such mechanisms: the time constraint that students face. We study the time-constrained dynamic mechanism (TCDM) theoretically and show that, under straightforward behavior, it can generate unstable outcomes and, in some cases, outcomes that are Pareto dominated by those produced by the student-proposing deferred acceptance mechanism (DA). We also compare students' assignment probabilities under TCDM and DA. Under this behavior, TCDM gives each student a weakly higher probability of receiving her first choice. Under universal acceptability and sufficient aggregate capacity, it also gives each student a weakly higher probability of remaining unassigned and a weakly lower probability of receiving a non-first-choice college.

econ.TH↗

arXiv2026

Rawlsian Assignments

We study the assignment of indivisible goods to individuals without monetary transfers. Existing literature has mainly focused on efficiency and individually fair assignments; consequently, egalitarian concerns have been overlooked. Drawing inspiration from the allocation of apartments in housing cooperatives, where families prioritize egalitarianism in assignments, we introduce the concept of Rawlsian assignment. We show that the Rawlsian assignment is unique and that the rule it induces is efficient and anonymous. The Rawlsian rule is not sd strategyproof, reflecting a fundamental incompatibility between worst-rank minimization and even weak incentive requirements. Nevertheless, it satisfies several robustness properties that limit other forms of manipulation. We illustrate our findings using cooperative housing preference data, showing significant improvements in egalitarian outcomes over both the probabilistic serial rule and the currently employed rule.

econ.TH↗

arXiv2026

Local non-bossiness

The student-optimal stable mechanism (DA), the most popular mechanism in school choice, is the only one that is stable and strategy-proof. However, when DA is implemented, a student can change the schools of others without changing her own. We show that this drawback is limited: a student cannot change her schoolmates while remaining at the same school. We refer to this new property as local non-bossiness and use it to provide a new characterization of DA that does not rely on stability. Furthermore, we show that local non-bossiness plays a crucial role in providing incentives to be truthful when students have preferences over their colleagues. As long as students first consider the school to which they are assigned and then their schoolmates, DA induces the only stable and strategy-proof mechanism. There is limited room to expand this preference domain without compromising the existence of a stable and strategy-proof mechanism.

econ.TH↗

arXiv2024

Respecting priorities versus respecting preferences in school choice: When is there a trade-off?

A classic trade-off that school districts face when deciding which matching algorithm to use is that it is not possible to always respect both priorities and preferences. The student-proposing deferred acceptance algorithm (DA) respects priorities but can lead to inefficient allocations. We identify a new condition on school choice markets under which DA is efficient. Our condition generalizes earlier conditions by placing restrictions on how preferences and priorities relate to one another only on the parts that are relevant for the assignment. Whenever there is a unique allocation that respects priorities, our condition captures all the environments for which DA is efficient. We show through stylized examples and simulations that our condition significantly expands the range of known environments for which DA is efficient. We also discuss how our condition sheds light on existing empirical findings.

econ.TH↗