There is a substantial number of cases where the a priori relationship between products is not at all clear in the sense that although apparent to be clear substitutes may turn out to be in fact complements, or vice-versa. This paper aims to study the relationship between fixed and mobile...

We analyze the incentives of a telecommunications incumbent to invest and give access to a downstream entrant to a next generation network, NGN. We model the industry as a duopoly, where a vertically integrated incumbent and a downstream entrant, that requires access to the incumbent's network,...