This paper concerns an industry with two complementary goods. It is demonstrated that if a good is active in Cournot equilibrium, then it is active in either one of the socially optimal solution and the monopoly solution; but, the converse is not true. When demands are linear, a good is active...

This study compares a differentiated Cournot duopoly with a two-product monopoly by using the socially optimal solution as a reference point. Each solution is allowedto be either an interior or a corner solution. We establish that the ranking regarding each individual price is clear-cut and...