Differentiated product consumption choices made without full information can lead to welfare losses from regret and missed opportunities, but a lack of post-purchase usage data has prevented their exploration. Using novel data on individual ownership and post-purchase usage of video games, we...

This paper analyzes the welfare implications of international spillovers related to productivity gains, changes in market size, or government spending. We introduce trade costs and endogenous varieties in a two-country general-equilibrium model with monopolistic competition, drawing a...

This paper presents a model of international trade that features heterogeneous firms, relative endowment differences across countries, and consumer taste for variety. The paper demonstrates that firm reactions to trade liberalization generate endogenous Ricardian productivity responses at the...

Can variants of the classic Calvo (1983) model of sticky prices account for the statistical behavior of post-war US inflation? We develop and test versions of the model for which the answer to this question is yes. We then investigate whether these models imply plausible degrees of inertia in...

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 examine the extent that product differentiation affects the duration of US import trade relationships. Applying nonparametric and semiparametric techniques to highly disaggregated product-level data we estimate that the hazard rate is at least 18 percent higher for homogenous goods than for...

Since the seminal work of Krugman (1979), product variety has played a central role in models of trade and growth. In spite of the general use of love-of-variety models, there has been no systematic study of how the import of new varieties has contributed to national welfare gains in the United...

We present a North South model of international trade in which differentiated products are developed in the North. Sectors are populated by final-good producers who differ in productivity levels. Based on productivity and sectoral characteristics, firms decide whether to integrate into the...

Roughly one-third of world trade is intrafirm trade. This paper starts by unveiling two systematic patterns in the volume of intrafirm trade. In a panel of industries, the share of intrafirm imports in total U.S. imports is significantly higher, the higher the capital intensity of the exporting...