We extend the theory of tax incidence under Cournot-Nash oligopolistic competition to study the effects of an ad valorem sales tax on Web services (so-called Web Tax) that are provided free of charge to users, and produce advertising space sold to businesses. Ads are more valuable to advertisers...

This report presents evidence on the relationship between online platforms and businesses using these platforms to reach consumers or conduct their operations. First, we review the literature on vertical relationships both from a classic approach and from a multi-sided market perspective....

This paper takes stock of recent developments related to online consumer ratings and reviews and their effects on consumer behaviour. It provides an overview of key consumer benefits and risks associated with user-generated feedback, and identifies consumer policy challenges, including...