Sept. 4 (HealthDay News) -- Trying to determine the best way to get people to cooperate, researchers at Harvard University and the Stockholm School of Economics have found that a carrot is better than a stick.

In certain situations "where people interact repeatedly with each other to solve a group social dilemma, our work suggests that rewards result in better outcomes than punishment," study lead author David G. Rand, a postdoctoral researcher at Harvard's Program for Evolutionary Dynamics, said in a university news release. "Rewards can change individuals' behavior and encourage cooperation without the destructive negative consequences that come with punishment."

The study authors noted that their research flies in the face of previous findings, which supported punishment as the best way to get people to cooperate.

The researchers recruited 192 people to take part in a "public goods" game designed to reveal how people interact when they must choose between their interests and those of a group.

The research team noted that study subjects resented "free riders" who failed to contribute to the group yet reaped benefits of being part of it.

"But despite this anger at free riders, rewarding good behavior is as effective as punishing bad behavior for maintaining public cooperation and leads to better outcomes for the group," Rand said. "When both options are available, reward leads to increased contributions and payoff for the group, while punishment has no effect on contributions and leads to lower payoff for the group."

The study findings appear in the Sept. 4 issue of the journal Science.

SOURCE: Harvard University, news release, Sept. 3, 2009