Digital platforms operate in multisided markets providing services through the internet to two or more distinct groups of users, between which there are indirect network effects. Direct network effects are frequently present within each group. Therefore, online platforms usually present both...

We consider a software vendor first selling a monopoly platform and then an application running on this platform. He may face competition by an entrant in the applications market. The platform monopolist can benefit from competition for three reasons. First, his profits from the platform...

We study how digital platforms can choose competitive strategies to influence the number of multihoming consumers. Platforms compete for consumers and advertisers. A platform earns a premium from advertising to singlehomers, as it is a gatekeeper to these consumers. Competitive strategies...

In many markets, user benefits depend on participation and usage decisions of other users giving rise to network effects. Intermediaries manage these network effects and thus act as platforms that bring users together. This paper reviews key findings from the literature on network effects and...

We compare a discriminatory pricing regime with a non-discriminatory regime in a competitive bottleneck model where content providers endogenously sort into single or multi-homers. We find that consumer prices rise when the share of single-homers increases in the non-discriminatory case, while...

For many products, platforms enable sellers to transact with buyers. We show that the competitive conditions among sellers shape the market structure in platform industries. If product market competition is tough, sellers avoid competitors by joining different platforms. This allows platforms to...

We build a model of the news market where advertisers allocate their ads between a social media platform and a news website. Our objective is to evaluate policy interventions aimed at fostering news creation by transferring revenues from social media to news websites already introduced in...

We review the economics of superstars, originally developed for stars in traditional media, and discuss whether they are applicable for the (allegedly) novel phenomenon of stars in social media (influencer, micro-celebrities). Moreover, we analyse potentially new factors for creating social...

This online appendix to "Insulated Platform Competition" includes proofs and details of our applications.The paper to which these Appendices apply is available at the following URL: "http://ssrn.com/abstract=1694317" http://ssrn.com/abstract=1694317

Does competition promote efficient platform pricing and market structures? We model imperfect platform competition using a new approach, Insulated Equilibrium (IE). Building on the observation that platforms often charge low prices to build a "critical mass", IE assumes platforms use...