Rigidity in bilateral trade with holdup
研究卖方进行隐藏投资影响买方隐藏估值的双边贸易，发现预算平衡机制无法同时实现最优贸易和最优投资，最优合同会导致贸易刚性，其程度取决于敲竹杠问题的严重性。
This paper studies bilateral trade in which the seller makes a hidden investment that influences the buyer's hidden valuation. In general it is impossible to implement both first-best efficient trade and efficient investment using budget-balanced trading mechanisms. The paper fully characterizes the constrained efficient contracts. It is shown that the optimal tradeoff between allocative efficiency and incentive provision results in rigidity in trade, the degree of which depends on the seriousness of the holdup problem. Sufficient conditions are also provided for full separation of buyer types to take place in optimal contracts when the holdup problem is not too severe. The seller may overinvest relative to the first best.