We examine merging firms' additions and removals of products for a sample of 66 mergers across a wide variety of consumer packaged goods markets. We find that mergers lead to a net reduction in the number of products offered by merging firms. Merging firms tend to both drop and add products at...

This paper investigates the effect of endogenous horizontal product differentiation on trade patterns and the gains from trade under Bertrand and Cournot oligopoly. Firms differentiate their products to mitigate competition, but only if the investment required is not too high. Investment in...

This paper provides a new and simple model of endogenous horizontal product differentiation based on a standard demand structure derived from quadratic utility. One objective of the paper is to explain the "empirical Bertrand paradox" - the failure to observe homogeneous product Bertrand...

We consider nonparametric identification in models of differentiated products markets, using only market level observables. On the demand side we consider a nonparametric random utility model nesting random coefficients discrete choice models widely used in applied work. We allow for...

We develop a framework for studying trade in vertically and horizontally differentiated products. In our model, consumers with heterogeneous incomes and tastes purchase a homogeneous good as well as making a discrete choice of quality and variety of a differentiated product. The distribution of...

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...

Not surprisingly, big countries trade more than small countries. In this paper we use data on shipments by 110 exporters to 59 importers in 5,000 product categories to ask: how? Do big countries trade larger quantities of a common set of goods (the intensive margin), a larger set of goods (the...