Incentives matter: Bin Laden file

From the New York Times

When children playing in the fields let a ball fly into the compound by mistake, the owners never let them retrieve it but gave them 50 rupees to buy a new one, said one of the neighbors, a woman with a small boy on her hip who gave her name only as Bibi. When the children began to throw balls into the compound on purpose to get more money, the owners kept paying, she said, laughing.