Joint Projects without Commitment
分析在没有承诺和可执行合约时，合作者交替为联合项目做贡献的博弈，发现唯一子博弈完美均衡路径可能导致社会合意的项目无法完成，而“订阅博弈”则能实现有效结果。
This paper concerns the pattern of contributions to a joint project when commitments and enforceable contracts are not available. We analyse a game in which partners alternate in making contributions to the project until the project is completed. Contributions are sunk when they are made. The game has a unique subgame perfect equilibrium path, which is inefficient in the sense that socially desirable projects may not be completed. By contrast, in a "subscription game" in which the cost of the contribution is borne only if and when the contributions committed to the project cover its cost, the outcome is efficient.