We show that deviations from long-run stability of product prices are optimal in the presence of endogenous producer entry and product variety in a sticky-price model with monopolistic competition in which price stability would be optimal in the absence of entry. Specifically, a long-run...

We analyze entry, pricing and product design in a model with differentiated products. Under plausible conditions, entry into an initially monopolized market leads to higher prices for some, possibly all, consumers. Entry can induce a misallocation of goods to consumers, segment the market in a...

This paper develops a model where firms make state-dependent decisions on both pricing and acquisition of information. It is shown that when information is not perfect, menu costs combined with the aggregate price level serving as an endogenous public signal generate rigidity in price setting...

The 2010 Department of Justice and Federal Trade Commission Horizontal Merger Guidelines lay out a new standard for assessing proposed mergers in markets with differentiated products. This new standard is based on a measure of ``upward pricing pressure,'' (UPP) and the calculation of a ``gross...

This is an invited chapter for the forthcoming Volume 4 of the Handbook of Industrial Organization. We present empirical models of demand and supply in differentiated products industries with an emphasis on the key ideas arising from the recent applied literature. We start with a discussion of...

This paper estimates a model of airline competition that captures the two major features of the industry: product differentiation and economies of density. The results not only provide support to some of the traditional common wisdom in the industry, but are also useful for understanding major...

This paper examines how prices set by multinational firms vary across arm's-length and related-party customers. Comparing prices within firms, products, destination countries, modes of transport and month, we find that the prices U.S. exporters set for their arm's-length customers are...

We document how demand shocks in export markets lead French multi-product exporters to re-allocate the mix of products sold in those destinations. In response to positive demand shocks, those French firms skew their export sales towards their best performing products; and also extend the range...

Empirical models of demand for-and, often, supply of-differentiated products are widely used in practice, typically employing parametric functional forms and distributions of consumer heterogeneity. We review some recent work studying identification in a broad class of such models. This work...

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...