This paper considers a market in which only the incumbent's quality is publicly known. The entrant's quality is observed by the incumbent and some fraction of informed consumers. This leads to price signalling rivalry between the duopolists, because the incumbent gains and the entrant loses when...

We study economies in which agents face Knightian uncertainty about state prices. Knightian uncertainty leads naturally to nonlinear expectations. We introduce a corresponding equilibrium concept with sublinear prices and prove that equilibria exist under weak conditions. In general, such...