Privately-Negotiated Input Prices

We examine settings where input prices are negotiated by industry suppliers, rather than dictated by regulators. We find that the input buyer may agree to pay a high price for an input because the high price serves to reduce the intensity of retail price competition with the input seller. Full exploitation of retail customers can result. However, retail price regulation, competition among buyers, and product heterogeneity all can limit the extraction of consumer surplus. We also identify conditions under which input price negotiations will fail to produce a mutually agreeable input price.We thank Dennis Weisman and two anonymous referees for very helpful commentsJEL classification: L43, L51, L22     

Games played in a contracting environment

We analyze normal form games where a player has to pay a price to a supplier in order to play a specific action. Our focus is on supplier competition, arising from the fact that distinct suppliers supply different players, and possibly different actions of the same player. With private contracts, where a player only observes the prices quoted by his own suppliers, the set of equilibrium distributions over player actions coincides with the set of equilibrium distributions when all actions are supplied competitively, at cost. With public contracts, the two distributions differ dramatically even in simple games.     

Games played in a contracting environment

We analyze normal form games where a player has to pay a price to a supplier in order to play a specific action. Our focus is on supplier competition, arising from the fact that distinct suppliers supply different players, and possibly different actions of the same player. With private contracts, where a player only observes the prices quoted by his own suppliers, the set of equilibrium distributions over player actions coincides with the set of equilibrium distributions when all actions are supplied competitively, at cost. With public contracts, the two distributions differ dramatically even in simple games.     

Costly horizontal differentiation

We study the effect of quadratic differentiation costs in the Hotelling model of endogenous product differentiation. The equilibrium location choices are found to depend on the magnitude of the differentiation costs (relatively to the transportation costs supported by consumers). When the differentiation costs are low, there is maximum differentiation. When they are high, there is partial differentiation, with a degree of differentiation that decreases with the differentiation costs. In any case, the socially optimal degree of differentiation is always lower than the equilibrium level. We also study the case of collusion between firms. If firms can combine locations but not prices, they locate asymmetrically when differentiation costs are high and choose maximum differentiation when they are low. When collusion extends to price setting, there is partial differentiation.     

Walrasian bargaining

Given any two-person economy, consider an alternating-offer bargaining game with complete information where the proposers offer prices, and the responders either choose the amount of trade at the offered prices or reject the offer. We provide conditions under which the outcomes of all subgame-perfect equilibria converge to the Walrasian equilibrium (the price and the allocation) as the discount rates approach 1. Therefore, price-taking behavior can be achieved with only two agents.     

Shopping hours and price competition

This paper develops an argument why retail prices may rise in response to the deregulation of opening hours. We make this point in a model of imperfect duopolistic competition. In a deregulated market retailers view the choice of opening hours as a means to increase the degree of perceived product differentiation thus relaxing price competition. If the consumers’ preference intensity for time is sufficiently high the equilibrium configuration has asymmetric shopping hours where one retailer stays open for longer than the other. Both retailers charge higher prices than under regulation, and both are strictly better off.     

Dissertation abstract: Essays on pricing in experimental duopoly markets

This dissertation comprises three independent essays that analyze pricing behavior in experimental duopoly markets. The first essay examines whether the content of buyer information and the timing of its dissemination affects seller market power. We construct laboratory markets with differentiated goods and costly buyer search in which sellers simultaneously post prices. The experiment varies the information on price or product characteristics that buyers learn under different timing assumptions (pre- and post-search), generating four information treatments. Theory predicts that price information lowers the equilibrium price, but information about product characteristics increases the equilibrium price. That is, contrary to simple intuition, presence of informed buyers may impart a negative externality on other uninformed buyers. The data support the model's negative externality result when sellers face a large number of robot buyers that are programmed to search optimally. Observed prices conform to the model's comparative statics and are broadly consistent with predicted levels. With human buyers, however, excessive search instigates increased price competition and sellers post prices that are significantly lower than predicted. The second essay uses experimental methods to demonstrate the anti-competitive potential of price-matching guarantees in both symmetric and asymmetric cost duopolies. When costs are symmetric, price-matching guarantees increase the posted prices to the collusive level. With asymmetric costs, guaranteed prices remain high relative to prices without the use of guarantees, but the overall ability of guarantees to act as a collusion facilitating device depends on the relative cost difference. Fewer guarantees, combined with lower average prices, suggest that cost asymmetries may discourage collusion. The third essay investigates the effect of firm size asymmetry on the emergence of price leadership in a homogeneous good duopoly. With discounting, the unique subgame-perfect equilibrium predicts that the large firm will emerge as the endogenous price leader. Independent of the level of size asymmetry, the laboratory data indicates that price leadership by the large firm is one of the most frequently observed timings of price announcement. In most cases, however, it comes second to simultaneous price-setting. This tendency to wait for the other firm to announce its price is especially strong when the level of size asymmetry between firms is low. We attribute the lower than expected frequency of price leadership to coordination failure, which is further compounded by elements of inequity aversion. JEL Classification C91, D43, D83, L11 Dissertation Committee: Timothy Cason (Chair), Department of Economics, Purdue University Dan Kovenock, Department of Economics, Purdue University Stephen Martin, Department of Economics, Purdue University Marco Casari, Department of Economics, Purdue University     

Existence and efficiency of a stationary subgame-perfect equilibrium in coalitional bargaining models with nonsuperadditive payoffs

We provide the existence theorem of stationary subgame-perfect equilibrium (SSPE) in a noncooperative coalitional bargaining game model with random proposers. Our model contains a bargaining situation where the coalitional game is nonsuperadditive. We also provide a necessary and sufficient condition for the existence of a pure-strategy SSPE satisfying the efficiency property when the discount factor is close to one. Furthermore, we provide examples where the delay in agreement occurs, even in a random-proposers model, when the game is nonsuperadditive. I am grateful to Akira Okada and an anonymous referee for their useful comments and helpful suggestions.     

Downstream mode of competition with upstream market power

In a two-tier oligopoly, where the downstream firms are locked in pair-wise exclusive relationships with their upstream input suppliers, the equilibrium mode of competition in the downstream market is endogenously determined as a renegotiation-proof contract signed between each downstream firm and its exclusive upstream input supplier. We find that the upstream–downstream exclusive relationships credibly sustain the Cournot (Bertrand) mode of competition in the downstream market, when the goods are substitutes (complements). In contrast to previous studies, this result holds irrespectively of the degree of product differentiation and the distribution of bargaining power between the upstream and the downstream firm, over the pair-specific input price.     

Skills scarcity and export intensity

We describe a model of trade with skills-based product differentiation and non-proportional trade costs that predicts a positive correlation between firms' export intensity, the price of their exports and the wages they pay to their workers. In equilibrium, firms that employ workers with comparatively scarcer skills export a larger proportion of their output, pay higher wages and charge higher prices. In line with empirical evidence, the model predicts that trade liberalization can cause the distribution of earnings to become more polarized, with patterns that reflect the heterogeneous effects of trade liberalization on firms' export performance.     

产品差别化、价格战与合谋

随着中国市场化改革的不断深入,价格战成为各行各业企业间不断上演的舞台剧。文章旨在从产品差别化与企业间合谋的相互关系出发,来分析企业频繁选择价格竞争而难以进行合谋的原因,即产品垂直差别水平的降低将使合谋难以维持,价格战容易爆发。因此,解决价格战的途径之一是中国企业应该加大自主创新的能力,提高产品垂直差别化程度。     

Product differentiation,price discrimination and collusion

The existing literature which analyses the relationship between the product differentiation degree and the sustainability of a collusive agreement on price assumes that firms cannot price discriminate, and concludes that there is a negative relationship between the product differentiation degree and the critical discount factor. This paper, in contrast, assumes that firms are able to price discriminate. Within the Hotelling framework, three different collusive schemes are studied: perfect collusion on discriminatory prices; perfect collusion on a uniform price; collusion not to discriminate. We obtain that the critical discount factor of the first and the third collusive scheme does not depend on the product differentiation degree, while the critical discount factor of the second collusive scheme depends positively on the product differentiation degree. Moreover, we show that imperfect collusion is more difficult to sustain than perfect collusion.     

VERTICAL DIFFERENTIATION AND THE DISTRIBUTION OF INCOME

The paper analyses the effects of income concentration on the behaviour of a duopoly with vertical product differentiation and uncovered market. By using a trapezoid distribution, we solve explicitly for market equilibrium as a function of a mean preserving spread of the income distribution. We show that overall more concentrated incomes imply stronger product differentiation, as the presence of a large share of middle‐income consumers stimulates a price competition, whose effects are dampened through an enlargement of the quality spread. While the high‐quality advantage and market coverage increase unambiguously in the degree of income concentration, the behaviour of prices is non‐monotone in the distribution parameter.     

标准专利许可中可变价格的社会福利效应:基于产品差异化的视角

技术标准在产品生产过程中的使用越来越广泛,标准专利许可定价形式问题关系到技术标准所有者和产品生产者的收益,有待拓展研究。通过构建古诺竞争模型,从产品差异化角度对标准专利许可中可变价格形式的社会福利效应进行分析,得到的主要结论为:当产品市场达到均衡,且标准专利许可采用的价格形式是可变价格时,社会总福利随着产品差异化程度的提高而增加,随着差异化产品市场中标准专利使用者数量的增加而增加,随着可变价格中可变费用比率的提高而降低;均衡产量随着产品差异化程度的提高而增大,随着可变价格中可变费用比率的提高而降低;均衡价格与产品差异化程度呈现出倒“U”型关系,临界点为特定的市场规模;标准专利使用者的均衡利润随着产品差异化程度的提高而增大。由此可见,标准专利许可的可变费用比率下降有利于激励技术标准使用者生产更多的差异化产品,提升社会总福利。     

Competition and confidentiality: Signaling quality in a duopoly when there is universal private information

We model non-cooperative signaling by two firms that compete over a continuum of consumers, assuming each consumer has private information about the intensity of her preferences for the firms' respective products and each firm has private information about its own product's quality. We characterize a symmetric separating equilibrium in which each firm's price reveals its respective product quality. We show that the equilibrium prices, the difference between those prices, the associated outputs, and profits are all increasing functions of the ex ante probability of high safety. If horizontal product differentiation is sufficiently great then equilibrium prices and profits are higher under incomplete information about quality than if quality were commonly known. Thus, while signaling imposes a distortionary loss on a monopolist using price to signal quality, duopolists may benefit from the distortion as it can reduce competition. Finally, average quality is lower since signaling quality redistributes demand towards low-quality firms.     

Price and Quantity Competition in a Differentiated Duopoly With Network Compatibility Effects

We consider the efficiency of price and quantity competition in a network products market, where we observe product compatibility with network externalities (hereafter, network compatibility effects). In particular, if network compatibility effects between firms are sufficiently asymmetric, the Cournot equilibrium is more efficient than the Bertrand equilibrium in terms of larger consumer, producer and total surpluses. Then, we consider an endogenous choice of the strategic variables, price and quantity. If the degree of network compatibility effects of the rival firm is larger (smaller) than the degree of product substitutability, then choosing prices (quantities) is a dominant strategy for the firm. Thus, if the network compatibility effects of both firms are larger (smaller), the Bertrand (Cournot) equilibrium arises. Furthermore, if the network compatibility effects between the firms are sufficiently asymmetric, the firm with a larger (smaller) network compatibility effect than a certain level of product substitutability chooses quantities (prices). In this case, the Cournot–Bertrand equilibrium arises, which is less (more) efficient than the Cournot equilibrium in terms of consumer (producer) surplus.     

Can green consumerism replace environmental regulation?—a differentiated-products example

This paper assumes that consumers are willing to pay an extra premium for a good if it has a low impact on the environment. We examine if a little dose of such idealistic behavior has a large impact on the market equilibrium, and to what extent it can replace the environmental regulation. The analysis is carried out in a model with product differentiation, where consumers differ in their preferences for product quality. Consumers’ willingness to pay the environmental premium may be uniformly or non-uniformly distributed. Green consumerism will only be modestly influential in both cases, despite the fact that product differentiation leads to relaxed competition and increased profits, and thereby creates leverage.     

Vertical Product Differentiation When Quality is Scarce: The Case of n > 2 Firms

This paper describes a model of vertical product differentiation in which more than two firms compete in quality and price. Quality is of fixed supply, so firms participate in an auction to attain it. Firms then simultaneously choose prices. The paper determines equilibrium bids in the quality auction and the Bertrand equilibrium prices. In equilibrium one firm attains all the units of quality, but pays a price such that it, like the minimum-quality firms, earns zero profits. Aggregate welfare is computed, and is shown to decrease as competition increases.     

On the “merger paradox” in price competition with asymmetric product differentiation

By assuming asymmetric product differentiation, we consider the “merger paradox” in price competition (or the incentive to collude in prices). We investigate whether the emergence of the merger paradox depends on the degree of product differentiation between firms. In particular, unlike Deneckere and Davidson (1985), we demonstrate that if the degree of product differentiation between the insider and outsider is sufficiently small, then they are strategic substitutes, and thus, the merger paradox arises in price competition.