Nash equilibria of repeated games with observable payoff vectors

We study a model of repeated games with imperfect monitoring where the payo ff vectors observable. In this situation, any profitable deviation is detec table by all the players but the identity of the deviator may be unknown. W e design collective punishments directed against the set of potential devia tors. A particular class of signals is studied for which a characterization of the set of equilibrium payoffs is obtained. Journal of Economic Literat ure Classification Numbers: C73. (C) 1999 Academic Press.