We demonstrate that demand uncertainty alone can lead to equilibrium product variety. We consider a simple environment in which when demand is certain, a social planner, a competitive market, and a monopolist would all offer a single product, but when demand is uncertain, a social planner, a...

We show that demand uncertainty leads to vertical product differentiation even when consumers are homogeneous. When a firm anticipates that its inventory or capacity may not be fully utilized, product variety can reduce its expected costs of excess capacity. When the firm offers a continuum of...

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...

Online retail gives consumers access to an astonishing variety of products. However, the additional value created by this variety depends on the extent to which local retailers already satisfy local demand. To quantify the gains and account for local demand, we use detailed data from an online...

Online retail gives consumers access to an astonishing variety of products. However, the additional value created by this variety depends on the extent to which local retailers already satisfy local demand. To quantify the gains and account for local demand, we use detailed data from an online...

We propose a demand estimation method that allows for a large number of zero sale observations, rich unobserved heterogeneity, and endogenous prices. We do so by modeling small market sizes through Poisson arrivals. Each of these arriving consumers solves a standard discrete choice problem. We...