The role of networks in antitrust investigations
指出反垄断调查通常只关注相关市场内的竞争压力，但竞争也可能来自其他市场，即使单个市场约束弱，整体也可能重要。通过简单例子和网络工具，展示了如何捕捉跨市场的系统性竞争，并以超市反垄断调查为例说明。
Abstract Antitrust investigations typically focus on the competitive pressures coming from within the defined markets of interest. However, competitive pressures can also come from other markets. Even when individually these markets place only weak constraints on one another, collectively they may matter. A networks approach to modelling competition permits a systemic view of competition that can sometimes paint a more accurate picture. We demonstrate this through some simple examples, and show more generally how tools from the networks literature can be applied to capture competition across a system of interrelated markets. As a leading example, we consider antitrust investigations into supermarkets where local geographic markets have been used as the basis of investigation.