One factor that determines whether individuals cooperate or compete is the nature of the situation itself. The characteristics of some social dilemmas lead them to produce a lot of competitive responses, whereas others are arranged to elicit more cooperation. Thus one way to reduce conflict, when the approach is possible, is to change the rules of the task to reinforce more cooperation (Samuelson, Messick, Rutte, & Wilke, 1984). A class in which the instructor has decided ahead of time that only 10% of the students can get an A will be likely to produce a competitive orientation among the students. On the other hand, if the instructor says that he or she would be quite happy to assign each student an A (assuming each individual deserves one!), a more cooperative orientation is likely to ensue. In general, cooperation will increase when it is more rewarded, and competition will increase when it is rewarded (Komorita & Parks, 1994).
If societies really desire to maintain the public goods for their citizens, they will work to maintain them through incentives—for instance, by creating taxes requiring each person to contribute his or her fair share to support them. A city may add a carpool lane to the roadways, making it more desirable to commute with others and thereby help keep the highways unclogged. Similarly, in terms of harvesting dilemmas, rules can be implemented that regulate the amount of the public good that can be taken by each individual member of the society. In a water crisis, rationing can be implemented in which individuals are allowed to use only a certain amount of water each month, thereby protecting the supply for all, or fishing limits can be imposed to maintain populations. People form governments in part to make sure that all individuals in the community contribute to public goods and obey the rules of cooperation. Leaders may also be elected by the group to help convince the members of the society that it is important just to follow the rules, thereby increasing cooperation (Tyler & Lind, 1992).