Private Relationships Drive Public Cooperation: A New Path to Collective Action.
The article shows that in a game where people can choose to help or not help others, contributions usually decrease over time. However, when people have personal relationships with each other, they can use these relationships to encourage good behavior in the group. By refusing to help those who don't contribute, individuals can support cooperation without needing to use punishments. The researchers found that these personal interactions can help increase contributions to the common pool in the game.