Efficient and nearly efficient partnerships

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.