Segmentation versus Agglomeration: Competition between Platforms with Competitive Sellers
研究了卖家之间的竞争条件如何影响平台市场结构：当产品市场竞争激烈时，卖家会分散到不同平台，使平台维持高费用；竞争缓和时，卖家集聚于单一平台，平台争夺主导地位。
For many products, platforms enable sellers to transact with buyers. We show \nthat the competitive conditions among sellers shape the market structure in platform \nindustries. If product market competition is tough, sellers avoid competitors \nby joining different platforms. This allows platforms to sustain high fees and explains \nwhy, for example, in some online markets, several homogeneous platforms \nsegment the market. Instead, if product market competition is soft, agglomeration \non a single platform emerges, and platforms fight for the dominant position. These \ninsights give rise to novel predictions. For instance, market concentration and fees \nare negatively correlated in platform industries, which inverts the standard logic of \ncompetition.