he Core in Games with egative Externalities
نویسندگان
چکیده
In this paper, we study games with externalities. In the presence of externalities, the worth of a coalition depends on the coalition itself and a partition of the player set. In the presence of externalities, superadditivity is no longer sufficient for the efficiency of the grand coalition: some partitions may yield more surplus than the grand coalition. This result was indicated by Hafalir (GEB 61:242-258, 2007), who proposed convexity as the sufficient condition. We attempt to extend the results of Hafalir and explore certain weaker sufficient conditions to achieve the efficiency of the grand coalition. Our approach features two types of externalities: positive and negative. Furthermore, we examine a condition for the non-emptiness of the core. In the presence of externalities, the definition of the core is not unique. In this light, we specifically analyze the optimistic core which is the smallest of all types of cores. We prove that a combination of negative externalities and particular conditions can induce the nonempty optimistic core.
منابع مشابه
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