{"ID":2884902,"CreatedAt":"2026-06-01T04:54:23.091178241Z","UpdatedAt":"2026-06-01T04:54:23.091178241Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2508.06685","arxiv_id":"2508.06685","title":"Inter-role reciprocity in evolutionary trust game on square lattices","abstract":"Simulating bipartite games, such as the trust game, is not straightforward due to the lack of a natural way to distinguish roles in a single population. The square lattice topology can provide a simple yet elegant solution by alternating trustors and trustees. For even lattice sizes, it creates two disjoint diagonal sub-lattices for strategy learning, while game interactions can take place on the original lattice. This setup ensures a minimal spatial structure that allows interactions across roles and learning within roles. By simulations on this setup, we detect an inter-role spatial reciprocity mechanism, through which trust can emerge. In particular, a moderate return ratio allows investing trustors and trustworthy trustees to form inter-role clusters and thus save trust. If the return is too high, it harms the survival of trustees; if too low, it harms trustors. The proposed simulation framework is also applicable to any bipartite game to uncover potential inter-role spatial mechanisms across various scenarios.","short_abstract":"Simulating bipartite games, such as the trust game, is not straightforward due to the lack of a natural way to distinguish roles in a single population. The square lattice topology can provide a simple yet elegant solution by alternating trustors and trustees. For even lattice sizes, it creates two disjoint diagonal su...","url_abs":"https://arxiv.org/abs/2508.06685","url_pdf":"https://arxiv.org/pdf/2508.06685v1","authors":"[\"Chaoqian Wang\",\"Wei Zhang\",\"Xinwei Wang\",\"Attila Szolnoki\"]","published":"2025-08-08T20:17:39Z","proceeding":"physics.soc-ph","tasks":"[\"physics.soc-ph\",\"cs.GT\",\"nlin.CG\"]","methods":"[\"Generative Adversarial Network\"]","has_code":false}