In the matching with contracts framework, under the assumption that each hospital has a choice function that satisfies the observable substitutability condition, we show that the strategy-proof cumulative offer mechanism is no longer guaranteed to be group strategy-proof, yet it nevertheless outputs a weakly Pareto efficient outcome for any input. We also discuss why, unlike the previous observations in the literature, the equivalence of strategy-proofness and group strategy-proofness does not carry over to our context.

中文翻译：

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团体激励相容性和福利以与合同匹配

在与合同匹配的框架中，假设每个医院都有满足可观察的可替代条件的选择功能，我们表明，策略防错的累积报价机制不再保证是团体策略防错的，但是仍然输出对于任何输入，帕累托有效结果均较弱。我们还讨论了为什么不同于文献中先前的观察，策略证明性和群体策略证明性的等效性不会延续到我们的上下文中。