Núñez, Marina (Núñez Oliva)Robles Jiménez, Francisco Javier2023-01-202023-01-202023https://hdl.handle.net/2445/192403We study the problem of allocating packages of different objects to a group of bidders. A rule is overbidding-proof if no bidder has incentives to bid above his actual valuations. We prove that if an efficient rule is overbidding-proof, then each winning bidder pays a price between his winning bid and what he would pay in a Vickrey auction for the same package. In counterpart, the set of rules that satisfy underbidding-proofness always charge a price below the corresponding Vickrey price. A new characterization of the Vickrey allocation rule is provided with a weak form of strategy-proofness. The Vickrey rule is the only rule that satisfies efficiency, individual rationality, overbidding-proofness and underbidding-proofness. Our results are also valid on the domains of monotonic valuations and of single-minded bidders. Finally, a rule is introduced that is overbidding proof and its payoffs are bidder-optimal in the core of the auction game according the reported valuations.22 p.application/pdfengcc-by-nc-nd, (c) Núñez, Marina et al., 2023http://creativecommons.org/licenses/by-nc-nd/3.0/es/Assignació de recursosEconomia de l'ofertaEconomia matemàticaTeoria de jocsResource allocationSupply-side economicsMathematical economicsGame theoryinfo:eu-repo/semantics/workingPaperinfo:eu-repo/semantics/openAccess