@techreport{8e2d3c679278418d92409ffc27ff937b,
title = "Pairwise efficiency and monotonicity imply Pareto efficiency in (probabilistic) object allocation",
abstract = "We consider object allocation problems with capacities (see, e.g., Abdulkadiroglu and Sonmez, 1998; Basteck, 2025) where objects have to be assigned to agents. We show that if a lottery rule satisfies ex-post non-wastefulness and probabilistic (Maskin) monotonicity, then ex-post pairwise efficiency is equivalent to ex-post Pareto efficiency. This result allows for a strengthening of various existing characterization results, both for lottery rules and deterministic rules, by replacing (ex-post) Pareto efficiency with (ex-post) pairwise efficiency, e.g., for characterizations of the Random Serial Dictatorship rule (Basteck, 2025), Trading Cycles rules (Pycia and Unver, 2017), and Hierarchical Exchange rules (Papai, 2000). ",
keywords = "econ.TH, cs.GT",
author = "Tom Demeulemeester and Bettina Klaus",
note = "27 pages, 5 figures",
year = "2025",
month = aug,
day = "7",
doi = "10.48550/arXiv.2508.05340",
language = "English",
series = "arXiv.org",
number = "2508.05340",
publisher = "Cornell University - arXiv",
address = "United States",
type = "WorkingPaper",
institution = "Cornell University - arXiv",
}