当正式合同不能强制执行，而当事人诉诸关系合同时，竞争如何影响市场结果?衡量关系契约和处理竞争内生性的困难使回答这个问题的尝试受挫。我们通过研究卢旺达咖啡行业上游农民和下游工厂之间的关系合同取得了进展。首先，我们确定了他们的关系契约的显著维度(在收获之前、收获期间和收获之后，在两个方向上提供不可强制执行的服务)，并通过对工厂和农民的原始调查来衡量它们。其次，我们利用工厂最优布局的工程模型来构建一个隔离竞争中地理决定变化的工具。以流域内工厂的适宜性为条件，我们发现被更适宜地区包围的工厂:(i)面临更多来自其他工厂的竞争;(ii)减少与农民的关系合同;(三)表现较差。与传统观点相反，一个额外的竞争工厂也(iv)使农民的情况更糟;(v)减少农民提供给磨坊的咖啡总量; and (vi) conditional on the farmer's distance from the mill, lowers relational contracts more for farmers close to the competing mill, suggesting that competition directly alters farmers temptation to renege on the relational contract. The finding that increased competition downstream leaves all producers -- including upstream producers -- no better-off suggests a potential role for policy in a second-best environment in which contracts are hard to enforce.
