In this experiment you are a part of a group of players. In every game you will be asked to decide if you cooperate or do not cooperate with the group. If the group succeeds, every member of the group gets a bonus. If the group fails, every member of the group pays a cost. The probability of success is proportional to the number of cooperating members (that is, the more members choose to cooperate, the bigger the probability of group success is). Nevertheless, cooperation has a cost that you have to pay in order to cooperate.

The game will be played 40 times.

At the end of the experiment you will be rewarded according to your performance: The highest 10% will be rewarded 30 NS. In addition, the highest 40% will be eligible for a lottery of two prizes of 100 NS each.