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Experiments that investigate the spontaneous emergence of money in laboratory societies rely on indefinitely repeated helping games with random matching (Camera et al., 2013; Camera and Casari, 2014). An important open issue is the lack of a general proof of existence of an equilibrium capable of supporting the efficient allocation under private monitoring, without money. Here, we fill this gap by offering a general proof, as well as by characterizing the efficient non-monetary equilibrium. This technique can be extended to study games with simultaneous actions.


ESI Working Paper 19-28

This paper later underwent peer review and was published as:

Camera, G., & Gioffré, A. (2019). Cooperation in indefinitely repeated helping games: existence and characterization. Journal of Economic Behavior & Organization, 200, 1344-1356.



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