“…Marketers, meanwhile, describe the difficultly of "crossing the chasm" to reach critical mass in product sales (Moore 1991), while economists and political scientists sometimes find evidence for bandwagon effects in voting behavior (Hong and Konrad 1998). Finally, in the collective action literature, Sugden (1984), Chong (1991), Lichbach (1996) and others highlight the importance of reciprocity in providing incentives to contribute; contributions are often matched with contributions, while defection is matched with defection. Formally, game theorists and others note that if individuals can contribute to public goods contingent upon other participants, they can sometimes "solve" the free rider dilemma (Carson and Mitchell 1989, Axelrod 1984, Cornes and Sandler 1986.…”