Partitioned Matching Games for International Kidney Exchange

01/30/2023
by   Márton Benedek, et al.
0

We introduce partitioned matching games as a suitable model for international kidney exchange programmes, where in each round the total number of available kidney transplants needs to be distributed amongst the participating countries in a "fair" way. A partitioned matching game (N,v) is defined on a graph G=(V,E) with an edge weighting w and a partition V=V_1 ∪…∪ V_n. The player set is N = {1, …, n}, and player p ∈ N owns the vertices in V_p. The value v(S) of a coalition S ⊆ N is the maximum weight of a matching in the subgraph of G induced by the vertices owned by the players in S. If |V_p|=1 for all p∈ N, then we obtain the classical matching game. Let c=max{|V_p| | 1≤ p≤ n} be the width of (N,v). We prove that checking core non-emptiness is polynomial-time solvable if c≤ 2 but co-NP-hard if c≤ 3. We do this via pinpointing a relationship with the known class of b-matching games and completing the complexity classification on testing core non-emptiness for b-matching games. With respect to our application, we prove a number of complexity results on choosing, out of possibly many optimal solutions, one that leads to a kidney transplant distribution that is as close as possible to some prescribed fair distribution.

READ FULL TEXT

Please sign up or login with your details

Forgot password? Click here to reset