An upstream firm with full commitment bilaterally contracts with two ex ante identical downstream firms. Each observes its own cost shock, and faces uncertainty from its competitor’s shock. When they are risk neutral and can absorb losses, the upstream firm contracts symmetric outputs for production efficiency. However, when they are risk averse, competition requires the payment of a risk premium due to revenue uncertainty. Moreover, when they enjoy limited liability, competition requires the upstream firm to share additional surplus. To resolve these trade‐offs, the upstream firm offers exclusive contracts in many cases.

中文翻译：

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具有下游风险规避或有限责任的垂直排除

具有完全承诺的上游公司与两个事前相同的下游公司签订了双边合同。每个人都会承受自己的成本冲击，并面临竞争对手的冲击带来的不确定性。当它们处于风险中性并且可以吸收损失时，上游公司会收缩对称的产出以提高生产效率。但是，当他们规避风险时，由于收入的不确定性，竞争需要支付风险溢价。而且，当它们承担有限责任时，竞争要求上游公司分享额外的盈余。为了解决这些折衷，上游公司在许多情况下提供独家合同。