摘要：This note studies second-degree discrimination by a platform that sells a two-version (online) service to consumers
engaged in a social network. Consumers choose between a premium version, which enhances network externalities, or
a free version, which includes advertising about some other product. Under the assumptions that the consumers'
valuations for the advertised product are uniformly distributed and that advertising has a signaling structure, we relate
optimal pricing to the underlying degree distribution and the hazard rate of the random network. We derive close form
expressions for the platform's profits in most prominent real-world social networks where online platforms operate.
Platforms that operate in large and relatively sparse networks wish to provide only the free version, whereas platforms
serving more densely connected networks prefer to provide both versions.
