Quantity vs. Quality and Exclusion by Two-Sided Platforms

It is common for two-sided platforms to deny participation to some potential customers, who would otherwise be willing to pay the platforms' access and/or transaction fees. Videogame console manufacturers such as Microsoft, Sony, and Nintendo, for example, restrict access to a select set of game developers and exclude many others by including security chips in their consoles, even though the latter would also be willing to pay the per-game royalties levied by the manufacturers. Apple routinely excludes certain application developers from its highly popular iPhone store. Professor Andrei Hagiu builds a simple model formalizing profit-maximizing two-sided platforms' choice of exclusion policies, which is fundamentally determined by a tradeoff between quality and quantity.

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