Hauser, John R.; Wernerfelt, Birger - In: Marketing Science 7 (1988) 1, pp. 92-93
This note provides a formal proof that for the Defender model, with uniformly distributed tastes, the Nash price equilibria exist and, for a given set of positions, that they are unique. We also show that the profit function is well-behaved—continuous and quasi-concave—and that the maximum...