Bertrand and Cournot Competition with Network Effects and Input Pricing Strategy

We revisit the endogenous choice of price or quantity made by two retailers in a vertical structure with a monopolistic manufacturer under network externalities when the retailers involve in centralized Nash bargaining with the two-part tariff contracts. When comparing integration to separation under Cournot and Bertrand competition, in contrast to conventional wisdom, we show that regardless of competition mode and the strength of network externalities, Pareto superiority can obtain under separation rather than under integration. Furthermore, we find the result that regardless of network externalities, Cournot emerges in equilibrium obtained under uniform input pricing, which is asserted to be in contrast with Basak and Wang (2016) showing that Bertrand emerges in equilibrium under discriminatory input pricing in the absence of network externalities. However, the irrelevance results hold in equilibrium: the levels of social welfare, retailers' and manufacturer's profits are equal irrespective of whether (i) input pricing strategy of the manufacturer with/without network externalities, or (ii) endogenous competition mode.