Entry and Vertical Differentiation

This paper analyzes the entry of new products into vertically differentiated markets where an entrant and an incumbent compete in quantities. The value of the new product is initially uncertain and new information is generated through purchases in the market. We derive the (unique) Markov perfect equilibrium of the infinite horizon game under the strong long run average payoff criterion. The qualitative features of the optimal entry strategy are shown to depend exclusively on the relative ranking of established and new products based on current beliefs. Superior products are launched relatively slowly and at high initial prices whereas substitutes for existing products are launched aggressively at low initial prices. The robustness of these results with respect to different model specifications is discussed. Classification-JEL: C72, C73, D43, D83 Keywords: Entry, Duopoly, Quantity Competition, Vertical Differentiation, Bayesian Learning,Markov Perfect Equilibrium, Experimentation, Experience Goods

Market coverage and the nature of product differentiation: a note

In this note, we analyze the equilibrium outcomes of pricing games with product differentiation in relation with the extent of market coverage. It is a received idea in the IO literature that the horizontal and vertical models of product differentiation are almost formally equivalent. We show that this idea turns out to be wrong when the full market coverage assumption is relaxed. We then argue that there exist two fundamentally different classes of address-models of differentiation, although their difference is not perfectly captured by the standard horizontal/vertical typology.price competition, product differentiation, vertical differentiation, horizontal differentiation

"Multiproduct Duopoly with Vertical Differentiation"

The paper investigates a two-stage competition in a vertical differentiated industry, where each firm produces an arbitrary number of similar qualities and sells them to heterogeneous consumers. We show that, when unit costs of quality are increasing and quadratic, each firm has an incentive to provide an interval of qualities. The finding is in sharp contrast to the single-quality outcome when the market coverage is exogenously determined. We also show that allowing for an interval of qualities intensifies competition, lowers the profits of each firm and raises the consumer surplus and the social welfare in comparison to the single-quality duopoly.

Product differentiation and vertical integration in presence of double marginalization

In this paper, we present a model of endogenous vertical integration and horizontal differentiation. There exists two output brands and two versions of the input. The only mean for output differentiation is the input version used in output production. Firms may choose to vertically integrate to produce internally the required input version at marginal cost, rather then to buy it at the market price, if that version is made available. We show that vertical mergers increase the possibility that output goods are differentiated. Moreover, this occurs when the cost to differentiate the input is high. On the other hand, vertical integration is detrimental for brand variety if the cost to differentiate inputs is negligible.horizontal differentiation, vertical agreements, successive Cournot oligopolies

Would you like to enter first with a low-quality good?

Using a two-period duopoly model with vertical differentiation, we show that there exists a unique subgame perfect equilibrium where the first entrant supplies a lower quality and gains higher profits than the second entrant. We also prove that this entry sequence is socially efficient.entry, vertical differentiation

Choice of new attributes in the 'Elimination by Aspects' duopoly

The "Elimination by aspects" (EBA) duopoly of product differentiation (Laurent, 2006a) was constructed from the discrete model of probabilistic choice worked out by Tversky (1972a,b). In this framework, an unique price equilibrium exists with a "differentiation by attributes", which embodies horizontal and vertical differentiations as possible special cases. This paper extends this analysis by studying a two-stage game in which firms choose the specific attributes of their product and then compete in prices. At the price equilibrium, the "competitive effect", present in pure vertical differentiation models, is replaced by a "differentiation effect" in this EBA duopoly. Subgame perfect Nash equilibria are shown to exist with exogenous costs but also with attributes-dependent unit and fixed costs. At the equilibrium, products are generally differentiated both horizontally and vertically. But a purely vertical outcome may also occur when costs of innovation are strongly convex or when consumers are very sensible to the price levels. When costs are endogenous, the social optimum is achieved for a pure horizontal differentiation. Thus, there is too much differentiation at the equilibrium: the vertical dimension induces a strong raise of prices, which also reduces the welfare.elimination-by-aspects ; product differentiation ; quality choices ; welfare analysis

Product Differentiation in Successive Vertical Oligopolies

This is a successive oligopoly model with two brands. Each downstream firm chooses one brand to sell on a final market. The upstream firms specialize in the production of one input specifically designed for the production of one brand, but they also produce the input for the other brand at an extra cost. We show that when more downstream firms choose one brand, more upstream firms will specialize in the input specific to that brand, and vice versa. Hence, multiple equilibria are possible and the softening effect of brand differentiation on competition might not be strong enough to induce maximal differentiation. The existence of equilibria and their welfare performance are also examined.Product differentiation, Vertical relationships, Oligopoly

Market coverage and the nature of product differentiation : a note

In this note, we analyze the equilibrium outcomes of pricing games with product differentiation in relation with the extent of market coverage. It is a received idea in the IO literature that the horizontal and vertical models of product differentiation are almost formally equivalent. We show that this idea turns out to be wrong when the full market coverage assumption is relaxed. We then argue that there exist two fundamentally different classes of address-models of differentiation, although their difference is not perfectly captured by the standard horizontal/vertical typologyprice competition, product differentiation