We develop a two-sided market model where both platforms and sellers charge buyers for access. When network effects are moderate, a dominant platform that attracts more sellers and buyers is more likely to arise. Compared to when platforms split the market equally, a dominant platform always leads to higher consumer surplus and total welfare. Moreover, both of these measures improve as network effects increase. Our results suggest that competition authorities should be cautious regarding complaints related to dominant platforms in two-sided markets, as they may be good for consumers.

中文翻译：

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占主导地位的平台对消费者有利吗？

我们开发了一种双边市场模型，平台和卖家都向买家收取访问费用。当网络效应适中时，吸引更多卖家和买家的主导平台更有可能出现。与平台平分市场相比，占主导地位的平台总是会带来更高的消费者剩余和总福利。此外，随着网络效应的增加，这两种措施都会得到改善。我们的结果表明，竞争主管部门应对与双边市场中的主导平台有关的投诉保持谨慎，因为它们可能对消费者有利。