Bertrand competition when firms hold passive ownership stakes in one another

We show that the Bertrand oligopoly model with cost asymmetries may admit multiple Nash equilibria when firms hold passive ownership stakes in each other. The equilibrium price may be as high as the monopoly price of the most efficient firm.     

ENDOGENOUS TIMING AND STRATEGIC CHOICE: THE COURNOT‐BERTRAND MODEL

Cournot establishes a Nash equilibrium to a duopoly game under output competition; Bertrand finds a different Nash equilibrium under price competition. Both treat the strategic choice variable (output versus price) and the timing of play as exogenous. We investigate Cournot‐Bertrand models where one firm competes in output and the other competes in price in both static and dynamic settings. We also develop a general model where both the timing of play and the strategic choice variables are endogenous. Consistent with the conduct of Honda and Scion, we show that Cournot‐Bertrand behaviour can be a Nash equilibrium outcome.     

Leadership and Privatisation in a Mixed Multi‐product Oligopoly: An Endogenous Timing Model

This paper examines both leadership choice and welfare consequences of privatisation in an endogenous timing mixed multi‐product oligopoly. It shows that a multi‐product firm undermines the welfare‐maximising efforts of a public firm by cross‐subsidising. The paper demonstrates that a unique subgame perfect Nash equilibrium emerges in a multi‐product market, in contrast to the multiple equilibria of a single‐product market. This unique equilibrium indicates that profit‐maximising private firms retain leadership while a welfare‐maximising public firm acts as a follower. Even on the off‐equilibrium path where the public firm acts as a leader, it rarely generates maximum social welfare. However, privatising the public firm usually harms social welfare and results in a different timing structure in equilibrium.     

Bertrand versus Cournot revisited

Summary. Bertrand criticized Cournot's analysis of the competitive process, arguing that firms should be seen as playing a strategy of setting price below competitors' prices (henceforth, the Bertrand strategy) instead of a strategy of accepting the price needed to sell an optimal quantity (the Cournot strategy). We characterize Nash equilibria in a generalized model in which firms choose among Cournot and Bertrand strategies. Best responses always exist in this model. For the duopoly case, we show that iterated best responses converge under mild assumptions on initial states either to Cournot equilibrium or to an equilibrium in which only one firm plays the Bertrand strategy with price equal to marginal cost and that firm has zero sales. Received: December 11, 1995; revised version October 2, 1996     

PRICE FLOORS AND QUALITY CHOICE

This paper studies effects of price floors in a simple model of vertical product differentiation. We find that even non‐binding price floor (i.e., minimum price set below the lowest Nash equilibrium price in the baseline model) can increase quality on the market, if the cost of quality is sufficiently low. Where a binding price floor does not increase the equilibrium quality, it makes consumers worse off. There is also a possibility of over‐investment into quality as a result of the binding minimum price.     

ENDOGENOUS TIMING IN QUALITY CHOICES AND PRICE COMPETITION

We modify the price‐setting version of the vertically differentiated duopoly model by Aoki (2003) by introducing an extended game in which firms noncooperatively choose the timing of moves at the quality stage. Our results show that there are multiple equilibria in pure strategies, whereby firms always select sequential play at the quality stage. We also investigate the mixed‐strategy equilibrium, revealing that the probability of generating outcomes out of equilibrium is higher than the probability of playing one Nash equilibria in pure strategies. In the alternative case with full market coverage, we show that the quality stage is solved in dominant strategies and therefore the choice of roles becomes irrelevant as the Nash and Stackelberg solutions coincide. With full market coverage and corner solution, the results show that the game has a unique subgame perfect equilibrium in pure strategies, where the high‐quality firm takes the lead in the quality stage.     

Organizational Structure and the Choice of Price versus Quantity in a Mixed Duopoly

We consider the choice of price/quantity of a public and a private firm in a mixed differentiated duopoly. First, we study the way in which the strategic choice of the market variable is affected by different given organizational structures (managerial or entrepreneurial) of the public and the private firm. Second, we investigate how the price/quantity choice interacts with the endogenous choice of the organizational structure, thus determining a subgame perfect equilibrium at which firms choose to behave as price‐setters and to adopt a managerial structure.     

Mixed duopoly: Differential game approach

This study formulates a dynamic mixed oligopoly model, in which a state‐owned public firm competes against a private firm over multiple periods. We adopt a differential game formulated by Fershtman and Kamien [Econometrica 55 (1987), pp. 1151–1164] and investigate how the dynamic competition affects the optimal privatization policy. We characterize the open‐loop Nash equilibrium (OLNE) and Markov‐perfect Nash equilibrium (MPNE). We show that in the MPNE, an increase in the degree of privatization has a nonmonotonic effect on the price, increasing it in a wide range of parameter spaces, which is in sharp contrast to the result in the OLNE or static analyses. We also find that the optimal degree of privatization is higher in the MPNE than that in the OLNE and static equilibrium. These results suggest that intertemporal strategic behavior changes the optimal privatization policy.     

A public firm in a model of spatial duopoly with price discrimination

We visit the role of privatization in the location decision of firms in an industry where no firm can produce all varieties demanded. We demonstrate that the Nash equilibrium locations are socially optimal, in the presence of a publicly owned firm, notwithstanding the degree of privatization.     

ANTIDUMPING,INTRA‐INDUSTRY TRADE,AND QUALITY REVERSALS

We examine an export game where two (home and foreign) firms produce vertically differentiated products. The foreign firm is more R&D efficient and is based in a larger and richer market. The unique (risk‐dominant) Nash equilibrium exhibits intra‐industry trade, and the foreign producer manufactures a higher‐quality product. When transport costs are low, unilateral dumping by the foreign firm arises; otherwise, reciprocal dumping occurs. For some parameters, a domestic antidumping policy leads to a quality reversal in the international market whereby the home firm becomes the quality leader. This policy is desirable for the implementing country, though world welfare decreases.     

Price or Quantity? A New Irrelevance Result for Mixed Markets

Earlier studies for mixed markets have established a series of so‐called irrelevance results. While previous results relate to the attainment of the first‐best allocation for welfare, we provide a new irrelevance result in terms of the choice of strategic variable in the product market. We show that regardless of whether a public or private firm is the market leader, the leader always chooses the price contract whereas the follower is indifferent between the price contract and the quantity contract. The identity of the leader and the follower firm is therefore irrelevant for the equilibrium mode of competition. Implications for economic models in mixed market settings emerge, which are also discussed.     

Endogenous Choice of Strategic Contracts in a Mixed Duopoly with Bargaining Over Managerial Delegation Contracts

We revisit the endogenous choice problem of strategic contracts for the public firm and the private firm in a managerial mixed duopoly with differentiated goods. We consider the situation wherein the managerial delegation contracts are determined by maximising social welfare within the public firm, which is equal to the objective function of its owner, and through bargaining over the content of managerial delegation contracts between the owner and manager within the private firm. We show that, in equilibrium, when the manager of the private firm has high bargaining power relative to that of the owner, the public firm chooses a price contract, while the private firm chooses a quantity contract. However, there is no equilibrium market structure under the pure strategic contract class when the manager has sufficiently low bargaining power relative to that of the owner.     

Cooperative R&D and Strategic Trade Policy with Bertrand Competition

This paper uses a strategic trade policy model to analyze the welfare effects from allowing cooperation in R&D when firms compete in a price‐setting game in the product market. A policy game between two governments is analyzed, where each government chooses a particular cooperative R&D policy in order to maximize national welfare. At the Nash equilibrium to this game only one government allows cooperation in R&D. This equilibrium is both individually and jointly optimal. International cooperation in R&D is superior to no cooperation in R&D but is inferior to the Nash equilibrium of the government policy game.     

Choosing price or quantity? The role of delegation and network externalities

We consider a differentiated duopoly and endogenise the firm choice of the strategy variable (price or quantity) to play on the product market in the presence of network externalities. We model this choice by assuming both competition between entrepreneurial (owner-managed) firms and competition between managerial firms in which market decisions are delegated from owners to revenue-concerned managers. While network externalities are shown not to alter the symmetric equilibrium quantity choice arising in the no-delegation case, sufficiently strong network effects allow us to eliminate the multiplicity of equilibria under delegation and lead to a unique equilibrium in which both firms choose price.     

Input Prices as Signals of Costs to a Downstream Rival and Customer

We consider a dual distribution channel in which a vertically integrated manufacturer competes with a downstream rival in a retail market and also sells an input to the rival. We use a signalling model with a continuum of types to examine a situation in which the manufacturer has private information on the production cost of its retail product. We show that in a separating equilibrium under Cournot (Bertrand) retail competition, the manufacturer signals the uncompetitiveness (competitiveness) of its firm by charging a smaller input price than the optimal price under complete information.     

QUANTITY VERSUS PRICE IN A HOMOGENEOUS PRODUCT DUOPOLY*

In a simple homogeneous product setting, the paper looks at the debate on whether firms should choose quantity or price as their strategic variable. It examines a two-stage game between firms with symmetric costs in which the firms choose the strategic mode of operation in the first period and then, in the second period, price or output are chosen simultaneously according to the mode chosen in the first stage. In this game it is possible to have two Nash equilibria where either both play in quantities or both play in prices. One firm choosing price and the other quantity can never be a Nash equilibrium in the two-stage game. Both choosing quantity is always a Nash equilibrium. Both choosing prices may be a Nash equilibrium only in some situations: the structure of the cost functions decides this issue.     

N‐FIRM OLIGOPOLY WITH GENERAL ISO‐ELASTIC DEMAND

In this note oligopoly with iso‐elastic demand is analysed. Unlike previous studies we consider general iso‐elastic demand rather than the case of unit elasticity. An n‐firm Nash‐Cournot equilibrium for the case of heterogeneous constant marginal costs is derived. The main result is a closed‐form solution that shows the dependency of the equilibrium on the elasticity of demand and the share of industry costs. The result has applications to a wide range of areas in oligopoly theory by allowing comparisons across markets with different elasticities of demand.     

The price normalization problem in imperfect competition and the objective of the firm

Summary. General equilibrium models of oligopolistic competition give rise to relative prices only without determining the price level. It is well known that the choice of a numéraire or, more generally, of a normalization rule converting relative prices into absolute prices entails drastic consequences for the resulting set of Nash equilibria when firms are assumed to maximize profits. This is due to the fact that changing the price normalization amounts to altering the objective functions of the firms. Clearly, the objective of a firm must not be based on price normalization rules void of any economic content. In this paper we propose a definition of the objective of a firm, called maximization of shareholders' real wealth, which takes shareholders' demand explicitly into account. This objective depends on relative prices only. Real wealth maxima are shown to exist under certain conditions. Moreover, we consider an oligopolistic market and prove the existence of a Nash equilibrium in which each firm maximizes the real wealth of its shareholders. Received: July 10, 1997; revised version: July 27, 1998     

OPTIMAL POLICY FOR PRODUCT R&D WITH ENDOGENOUS QUALITY ORDERING: ASYMMETRIC DUOPOLY*

We examine the optimal R&D subsidy/tax policy under a vertically differentiated duopoly. In a significant departure from the existing work, we consider the case of asymmetric costs of product R&D where there is a small technology gap between firms. In our analysis, the endogeneity of quality ordering is explicitly taken into account. We demonstrate the possible anti‐leapfrogging effect of R&D subsidy/tax policy. By committing to a firm‐specific subsidy schedule contingent on firms’ quality choices, the government can not only correct distortions in product quality but also select the socially preferred equilibrium. The latter role is fulfilled by preventing the technologically inferior firm from becoming a quality leader in the industry. Both Bertrand and Cournot cases are analysed.     

Endogenous price leadership

We consider a linear price setting duopoly game with differentiated products and determine endogenously which of the players will lead and which one will follow. While the follower role is most attractive for each firm, we show that waiting is more risky for the low cost firm so that, consequently, risk dominance considerations, as in Harsanyi and Selten (A General Theory of Equilibrium Selection in Games, MIT Press, Cambridge, MA, 1988), allow the conclusion that only the high cost firm will choose to wait. Hence, the low cost firm will emerge as the endogenous price leader.