We demonstrate that demand uncertainty can explain equilibrium product variety in the presence of sunk costs. Product variety is an efficient response to uncertainty because it reduces the expected costs associated with excess capacity. We find that within the firm's product line, the highest...

This paper examines whether exporting activity matters for firm's price cost margins. The recent literature on exporting and productivity shows that exporters on average are more efficient than nonexporters. If that is the case we may also expect them to have different mark-ups. We investigate...