Caso 9: Spending on advertising In a context of rivalry. Empirical evidence suggests that the impact of one company's advertising on rivals differs across sectors. Al one extreme could be the cigarette industry. Roberts & Samuelson (1988) find that cigarette advertising is "cooperative", in the sense that it increases the size of the global cigarette market but does not change the market shares of each company very much. At the other extreme Is the cola industry, Gasmi, Laffont & Vuong (1992) find that the profit for each company from its advertising comes from the losses of rivals, but has almost no effect on the global demand for cola. 1.. What situation can competition in advertising among cola companies lead to? Does it extend to cigarette companies? Why? 2.. If the possibility of banning advertising is discussed, which companies in these two sectors would most likely be against it and which would be in favor of the ban