Doctoral Dissertation Research in Economics: Merger Analysis of Multisided Platforms: An Application to the Used Heavy Duty Truck Auction Market

该项目旨在检验市场竞争对提供多边平台的公司的影响的经济理论。多边平台促进两组或多组参与者之间的互动。例如，一家出售拍卖服务的公司正在将卖家与买家联系起来。该项目将开发新的经济理论，并将使用美国二手重型卡车拍卖销售的数据来测试该理论。数据分析将研究该行业先前特定合并的影响，以了解合并是否以及如何减少竞争。本项目中开发的方法也可用于研究多边平台公司之间竞争的其他市场。美国的政策制定者被要求评估拟议的合并，以确定合并是否会减少竞争。这对这类合并来说是一项艰巨的任务，因为评估必须考虑到平台如何互动以及合并可能如何改变互动。本项目将开发并演示一种评估这些因素的方法。保持和加强竞争可以增强美国整体经济。该项目将扩展现有的多边平台理论模型，包括平台之间的横向差异和商品之间的纵向差异。根据该项目构建的模型，平台沿着合并收取的更高费用对拥有不同质量水平商品的卖家产生了异质性影响。当这些平台上的群体之间存在不同的间接网络效应时，可以引发跨平台的质量结构变化。如果平台之间的横向差异更小，这种结构变化就更显著，这可以使参与者的数量对费用和间接网络效应更具弹性。这些发现与从美国二手重型卡车拍卖市场收集的交易数据一致。从数据来看，线下平台销售的优质货车比线上平台销售的货车价值更高。在领先的线下和在线拍卖平台合并后，线下平台收取更高的费用，并使用跨平台的信息政策来减少两个平台之间的搜索摩擦。这些政策变化影响了买卖双方的决策，导致这两个平台的质量结构发生变化：低质量的卡车更容易在线上平台交易，而高质量的卡车则倾向于在线下平台交易。这些平台上的交易价格差异变得比以前更加显著。该项目将重点关注合并可能导致的市场演变。在基于模型进行结构性估计后，该项目将调查合并对不同群体的福利影响，并展示几种提高平台收入或社会福利的方法。本项目中使用的方法和结果在市场具有垂直差异化商品时特别有用，例如健康保险市场和点对点贷款市场。该项目可以帮助我们了解合并对这些市场中不同群体的潜在异质性影响。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project is designed to test economic theories about the effects of market competition on firms providing multisided platforms. A multisided platform facilitates interactions between two or more groups of participants. For example, a firm that sells auction services is connecting sellers with buyers. This project will develop new economic theory and will test the theory using data from auction sales of used heavy-duty trucks in the United States. The data analysis will examine the effects of a specific previous merger in this industry to see if and how the merger reduced competition. The methods developed in this project can also be used to examine other markets with competition between between multisided platform firms. Policymakers in the US are asked to evaluate proposed mergers to determine whether the merger might reduce competition. This is a difficult task for these types of merger, since the evaluation has to take into account both how the platforms interact and how the merger might change interactions. This project will develop and demonstrate one way to evaluate these factors. Preserving and strengthening competition strengthens the U.S. economy as a whole.The project will extend the existing theoretical models of multisided platforms by including both horizontal differentiation between platforms and vertical differentiation among goods. According to the model constructed in the project, the higher fees charged by the platforms along with the merger have a heterogeneous impact on sellers with goods at different quality levels. When there are different indirect network effects among the groups on these platforms, it can trigger a change of quality structure across platforms. This structural change is more significant if there is less horizontal differentiation between platforms, which can make the number of participants more elastic to the fees and the indirect network effect. These findings are consistent with transaction data collected from the U.S. used heavy-duty truck auction market. According to the data, the high-quality trucks sold on the offline platform are valued more than the ones sold on the online platform. After the merger of the leading offline and online auction platforms, the offline platform charges a higher fee and uses a cross-platform information policy to reduce the search friction across the two platforms. These policy changes affect the decisions of buyers and sellers, resulting in a quality structure change on these two platforms: low-quality trucks are more likely to be transacted on the online platform, and high-quality trucks tend to be transacted on the offline platform. The difference in transaction prices on these platforms becomes more significant than before. The project will focus on this possible market evolution caused by the merger. After performing a structural estimation based on the model, the project will investigate the welfare implication of the merger on different groups and show several ways to improve the platform's revenue or social welfare. The method and results used in this project are especially useful when the markets have vertically differentiated goods, such as the health insurance market and the peer-to-peer lending market. The project can help us to understand the potential heterogeneous impact of mergers on different groups in those markets.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.