We examine communication in a 2-player sequential public good game in which the leader has private information about … deciding whether or not to contribute. Without communication, the unique equilibrium is fully efficient. We study whether the … introduction of communication about returns can destroy efficiency. Communication can be precise (about the exact return), or vague …

. We experimentally examine the influence of social distance and communication on ORPs in four countries. We demonstrate … strong evidence that personal but irrelevant communication significantly increases ORPs …

before making a choice. There are two possible explanations for this "communication effect". One is that communication … enhances group identity, the other is that communication elicits social norms. I discuss both views and argue in favor of a …