Polluted rivers are harmful to human, animals and plants living along it. To reduce the harm, cleaning costs are generated. However, when the river passes through several different countries or regions, a relevant question is how should the costs be shared among the agents. Ni and Wang (2007)...

We investigate a novel continuous-time mechanism in a public-goods game. Within a fixed period, a clock ensures that contributions increase simultaneously for every player, and players can choose when to stop, while their actions are observed by others in real time. We show both theoretically...