The study looked at how economic incentives and social preferences affect people's behavior. They used contests with different types of rewards and social benefits to test this. They found that when there is more competition and a public good involved, people bid more. But when there is strong competition and a public good, bids decrease. This shows that economic incentives can sometimes make people less likely to act in a pro-social way. It suggests that when designing rewards, we should consider people's social preferences to get the best results.