Carrots seem to go a much longer way than sticks when it comes to building team work and cooperation, according to a latest study.

Previous studies have focused almost exclusively on punishment for promoting cooperation but the one by Harvard and Stockholm School of Economics (SSE) researchers says that rewards are much more successful.

Rewards robustly build compliance and cooperation and could help in developing solutions for thorny problems requiring the cooperation of large numbers of people to achieve a greater good.

Researchers used a computer-based public goods game, a classic experiment for measuring collective action in a lab setting.

Study co-author David G. Rand, a researcher at Harvard University Program for Evolutionary Dynamics, says the work has implications far beyond subjects' behaviour in a computer game.

Rand and colleague Martin A. Nowak from Harvard's Program, examined cooperation among 192 participants in a public goods game probing the fundamental tension between the interests of an individual and a group.

'All of us engage in public goods games, on both large and small scales,' Rand says. 'Climate change is a huge public goods game: If each person does his or her part to conserve energy and reduce carbon dioxide emissions, it benefits us all.'

'On a more local level, public goods games include volunteering on school boards, helping to maintain public facilities in your community, or cleaning up after yourself and doing your share of work at the office,' says Rand.

'Rewards can change individuals' behaviour and encourage cooperation without the destructive negative consequences that come with punishment,' Rand concludes.

These findings were published in Science.