We introduce a general objective function, which incorporates competitive s
ituations, such as conservative, punitive, and predatory advertising. Linki
ng together the particular situations into a two-parameter family of max-mi
n problems, and using the Lanchester model to describe the dynamics of the
market, a bilinear-quadratic differential game is obtained. For this game,
we find saddle-point feedback time-invariant advertising strategies and sho
w when these strategies are Nash equilibrium strategies. In an empirical ap
plication involving duopolistic competition in the cola market, we find evi
dence of a punitive motivation for the advertising strategies.