Efficient and Nearly-Efficient Partnerships
证明确定性合伙关系中搭便车对效率的损害可能小于普遍认知，给出了维持完全效率的充要条件，并说明在广泛合伙关系中可通过混合策略均衡实现近似效率。
This paper shows in two ways that the degree to which free-riding diminishes the performance of deterministic partnerships may be less than has been generally thought. First, a necessary and sufficient condition is provided for a partnership to sustain full efficiency. It implies that many non-trivial partnerships sustain efficiency, such as generic ones with finite action spaces, and neoclassical ones with Leontief technologies. Second, approximate efficiency is shown to be achievable in a large class of partnerships, including ones with smooth and monotonic production and disutility functions. Approximate efficiency is achieved by mixed-strategy equilibria: one partner takes, with small probability, an inefficient action. The degree to which efficiency is approximated is restricted only by the amount of liability the partners can bear. Nonetheless, their equilibrium payments are not arbitrarily large.