Competition in some product markets takes the form of a contest. If some firms cooperate in such markets, they must decide how to allocate effort on each of their products and whether to reduce the number of their products in the competition. We show how this decision depends on the convexity...

Consumers may observe previous consumers’ choices. They may follow their choices if they think these consumers are better informed. In turn, firms may concentrate on influencing the early consumers. This, in turn, changes the nature of early consumers’ choice behavior as a signal for other...