Public good games provide an interesting testbed for the study of social dilemmas. Social dilemmas are inherent in decision making. Despite the diversity of dilemmas, all share the same structure: each individual benefits from behaving selfishly but a group gets greater rewards if its members cooperate.
In a typical public good game, players may divide their initial endowments into both a private account and a group account. The frequent strategy for a rational player is defection but most participants in public good experiments do cooperate to some extent. Factors that enhance cooperation are the communication among players or the payoff structure of the game. Nowadays it is thought that behavioral investments could be an important determinant of cooperation in social dilemmas. Participants´ endowments are distributed asymmetrically among a group to discover whether "rich" individuals will contribute more than poor individuals. The conclusion is that the differences in the level of contributions may be reduced if positions are assigned on the basis of merit rather than chance. Although asymmetries in participants´ behavioral investments (for instance, effort investments) affect fairness judgments and group identification, members are often not aware of such differences. But the origin of the endowments affects contribution levels in the public good game (Muehlbacher and Kirchler, 2009). Subjects who earned their endowments through a greater amount of effort were less cooperative than those individuals who had earned the money with ease.
