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...

E-commerce has grown considerably in recent decades and has had a disruptive impact on the retail industry. In this context, Amazon, one of the major players in (online) retailing and beyond, has been able to expand its business activities continuously in many countries. The present case study...