Econ Papers Daily / 期刊论文
网络结构与并购效率收益：来自美国货运铁路的证据
Network Structure and the Efficiency Gains from Mergers: Evidence from U.S. Freight Railroads
摘要
The trade-off between market power and efficiency gains is central to antitrust analyses of mergers, but empirical evidence quantifying efficiencies remains limited. Using transaction-level data from U.S. freight railroads (1985–2005), this article quantifies merger-induced cost efficiencies, driven mainly by eliminating inter-railroad interchange costs and reoptimization of routing and resource allocation within integrated networks. I develop a spatial equilibrium model with oligopolistic competition to assess equilibrium merger effects. Counterfactual analyses show mergers reduce shipment costs by 12.9% and prices by 8.8%. Markups increase by 7.2%, driven primarily by non-merging firms reallocating resources away from regions where merged firms achieve large cost reductions.
中文摘要
市场势力与效率提升之间的权衡是并购反垄断分析的核心问题，但量化效率的实证证据仍然有限。利用美国货运铁路的微观交易数据（1985-2005年），本文量化了并购带来的成本效率，这些效率主要源于消除铁路间换装成本以及整合网络内路线和资源配置的重新优化。我构建了一个包含寡头竞争的空间均衡模型，以评估并购的均衡效应。反事实分析显示，并购使运输成本降低12.9%，价格下降8.8%。加成率上升7.2%，主要驱动因素是非并购企业将资源从并购企业实现大幅成本降低的区域重新配置出去。