Original ResearchPublished 13 January 2026Integrating upstream and downstream reciprocity stabilizes cooperator-defector coexistence in others-only public goods gamesTatsuya Sasaki · Satoshi Uchida · Isamu Okada · Hitoshi Yamamoto · Yutaka NakaiFrontiers in Behavioral Economicsdoi 10.3389/frbhe.2025.1697570
Behavioral EconomicsPublished 7 March 2025Cooperation beyond group boundaries is evaluated differently depending on the existence of intergroup competitionWakaba Tateishi · Nobuyuki TakahashiFrontiers in Behavioral Economicsdoi 10.3389/frbhe.2025.1493427
