If buyers do not observe the quality of a product and production of quality is costly, market allocations can be very inefficient. Certification intermediaries are institutions that provide information about quality to buyers. The amount of information in the market determines the incentives...

In this paper we extend the model of vertical product differentiation to also consider information disparities about the extent of quality differences. Equilibrium prices turn out to depend not only on the share of informed consumers but also on uninformed consumers beliefs about quality...