We consider a two-agent, single indivisible object allocation problem. We focus on continuous mechanisms that satisfy agent sovereignty, and investigate implications of group strategyproofness. In particular, we provide an explicit characterization of the strategyproof mechanisms and show that there are non-affine maximizer mechanisms that do not belong to the class characterized by Roberts (North-Holland, 1979). Further, we show that there are no budget-balanced strategyproof mechanisms. Also, we obtain an impossibility for existence of strong group strategyproof mechanism. We find that this impossibility goes away upon relaxing our notion of group strategyproofness, and consequently, present a class of weak group strategyproof mechanisms. Finally, we completely characterize the class of feasible strategyproof mechanisms satisfying individual rationality, and show that there are no optimal strategyproof expected revenue maximizing mechanisms under a general class of well behaved type distributions.

中文翻译：

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论团队策略验证和最优对象分配

我们考虑一个两主体，单个不可分割的对象分配问题。我们关注于满足代理人主权的连续机制，并研究了集团战略证明的含义。特别是，我们提供了对策略验证机制的显式描述，并表明存在不属于罗伯茨（Roberts）（North-Holland，1979）的类的非仿射最大化器机制。此外，我们表明没有预算平衡的策略证明机制。同样，我们也无法建立强大的团体战略证明机制。我们发现，这种可能性随着放松我们的团队战略证明概念而消失了，因此，提出了一类薄弱的团队战略证明机制。最后，