Groupstrategyproofness of the egalitarian mechanism for constrained rationing problems, mimeo,

Abstract Motivated by applications in many economic environments, Bochet et al. The key contribution of the paper is a comprehensive study of the egalitarian mechanism with respect to manipulation by a coalition of agents. Our main result is that the egalitarian mechanism is, in fact, peak group strategyproof : no coalition of agents can (weakly) benefit from jointly misreporting their peaks. Furthermore, we show that the egalitarian mechanism cannot be manipulated by any coalition of suppliers (or any coalition of demanders) in the model where both the suppliers and demanders are agents. Our proofs shed light on the structure of the two models and simpify some of the earlier proofs of strategyproofness. An implication of our results is that the well known algorithm of Megidd