Beneficial Long Communication in the Multi-Player Electronic Mail Game

In the two-player electronic mail game (EMG), as is well-known, the probability of collective action is lower the more confirmations and re-confirmations are made available to players. In the multi-player EMG, however, as we show players may coordinate on equilibria where they require only few of the available confirmations from each other to act. In this case, increasing the number of available may either create equilibria with positive probability of collective action when none existed before, or may increase the probability of collective action, if equilibria with positive probability of collective action already existed for fewer available confirmations.