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Title: First-Choice Maximality Meets Ex-ante and Ex-post Fairness
For the assignment problem where multiple indivis- ible items are allocated to a group of agents given their ordinal preferences, we design randomized mechanisms that satisfy first-choice maximality (FCM), i.e., maximizing the number of agents as- signed their first choices, together with Pareto- efficiency (PE). Our mechanisms also provide guarantees of ex-ante and ex-post fairness. The generalizedeager Boston mechanism is ex-ante envy-free, and ex-post envy-free up to one item (EF1). The generalized probabilistic Boston mech- anism is also ex-post EF1, and satisfies ex-ante ef- ficiency instead of fairness. We also show that no strategyproof mechanism satisfies ex-post PE, EF1, and FCM simultaneously. In doing so, we expand the frontiers of simultaneously providing efficiency and both ex-ante and ex-post fairness guarantees for the assignment problem.  more » « less
Award ID(s):
2106983 2007994
PAR ID:
10466788
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
IJCAI
Date Published:
Format(s):
Medium: X
Location:
Macao, China
Sponsoring Org:
National Science Foundation
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