Rejection-proof mechanisms for multi-agent kidney exchange
研究了多主体肾脏交换中防止主体拒绝交换的机制，提出抗拒绝机制类，证明最优问题计算困难，并给出启发式解法，实验表明该机制能抑制事前策略行为。
Kidney exchange programs (KEPs) increase kidney transplantation by facilitating the exchange of incompatible donors. Increasing the scale of KEPs leads to more opportunities for transplants. Collaboration between transplant organizations (agents) is thus desirable. As agents are primarily interested in providing transplants for their own patients, collaboration requires balancing individual and common objectives. In this paper, we consider ex-post strategic behavior, where agents can modify a proposed set of kidney exchanges. We introduce the class of rejection-proof mechanisms, which propose a set of exchanges such that agents have no incentive to reject them. We provide an exact mechanism and establish that the underlying optimization problem is Σ2P-hard; we also describe computationally less demanding heuristic mechanisms. We show rejection-proofness can be achieved at a limited cost for typical instances. Furthermore, our experiments show that the proposed rejection-proof mechanisms also remove incentives for strategic behavior in the ex-ante setting, where agents withhold information.