Bilateral Oligopoly,Private Information,and Pollution Permit Markets

We analyze the effects of strategic behavior and private information in pollution permit markets in which all firms have market power. The market is characterized by supply-function equilibria. Firms submit net supplies for permits and a market maker determines the market-clearing price. Net supplies depend on abatement cost functions, which in turn depend on private information parameters. We calculate the increase in aggregate abatement costs due to strategic behavior and private information and show that private information attenuates the effects of strategic behavior.      

Price ceilings and firm-specific quantity restrictions in posted-offer markets

The effect of price ceilings and quantity controls in experimental posted-offer markets on market efficiency and total output is compared. Quantity controls adversely affect market performance relative to price ceilings. In the quota experiments contract and total surplus realization is lower than under equivalent price controls. Welfare outcomes, in terms of market efficiency, for price ceilings and quantity controls in a market setting are not the same, at least in the short run. Different welfare outcomes from equivalent controls are attributed to the manner in which the price and quantity search space is ‘censored’ by the price and quantity controls.     

Inflation,price dispersion and market integration through the lens of a monetary search model

Monetary search theory implies that the real effects of inflation via its impact on price dispersion depend on the level of search costs and, thus, on the level of market integration. For less integrated markets, the inflation–price dispersion nexus is predicted to be asymmetrically V-shaped which results in an optimal inflation rate above zero. For highly integrated markets with low search costs, however, the impact of inflation on price dispersion should only be small. Using price data of the European Union member states, this paper tests and confirms these predictions of monetary search theory.     

The effects of market organization on conspiracies in restraint of trade

Mindful of the market structure-conduct-performance paradigm fundamental to industrial organization research, this paper uses laboratory experimental techniques to study the impact of conspiratorial opportunities on market performance. We compare ‘posted-offer’ markets where sellers (but not buyers) are all conspiratorial opportunities with observations from three control groups: (1) posted-offer markets without conspiratorial opportunities, (2) ‘double-auction’ markets with conspiratorial opportunities and (3) posted-offer markets with true single-seller monopolists. The basic conclusions generated by our experimental design are: (1) seller conspiracies in posted-offer markets tend to raise prices (but not profits) relative to similarly organized markets without conspiracies, (2) posted-offer conspiracies tend to generate higher prices (but not profits) than double-auction conspiracies, and (3) posted-offer monopolies tend to generate higher profits (but not prices) then posted-offer conspiracies.     

Search less for a better price

In many markets, sellers must spend resources to learn the costs of providing goods/services. This paper considers consumer searches in such markets. The findings show that: (i) even with ex ante identical consumers and sellers, there is price dispersion in the equilibrium, (ii) despite price dispersion and minimal search costs, it could be optimal to search just two sellers and (iii) the optimal number of searches can increase with sellers' information costs.     

The effects of rent asymmetries in posted offer markets

We report the results of six posted-offer market experiments designed to analyze the effects of asymmetric supply and demand configurations on the price convergence path to competitive equilibrium. The posted-offer experiments are compared with twelve double-auction experiments reported by Smith and Williams (1982). Results differ markedly across trading institutions. Unlike trading under double-auction rules, we cannot reject the proposition that contract price convergence paths are unaffected by the distribution of consumer and producer surplus. Posted-offer contract prices tend to converge to the competitive equilibrium from above regardless of the distribution of the exchange surplus.     

Search costs and the severity of adverse selection

In view of some recent empirical evidence, I suggest a relationship between the magnitude of search costs and the severity of adverse selection in the context of a dynamic model with asymmetric information. In markets with small search costs sellers with low quality products misrepresent their quality and demand a high price. If search costs are not negligible, sellers׳ price offers are truthful and all product qualities are traded over time. In markets with small search costs, a budget balanced mechanism can mitigate adverse selection: sellers should pay a per period market participation tax and receive a rebate after trading.     

金融资产定价异常现象研究综述及其对新资产定价理论的启示

论文首先通过建立模型分析了在不同知情消费者比例下价格离散的结构形式,理论剖析了在搜索成本明显下降的电子商务市场,价格离散仍然持续存在的客观原因;进而运用在北京地区的93家电子商务零售网站、9大类535款商品、6313个价格样本数据检验了中国电子商务市场价格离散的情况,研究了其价格离散成因。结果表明在电子商务市场上,价格离散将持续存在,知情消费者比例与价格离散指标之间并不是一个单调关系;零售商特征,尤其是市场特征影响价格离散,各类零售商的定价依据不同。     

Maximum likelihood estimation of search costs

In a recent paper Hong and Shum [2006. Using price distributions to estimate search costs. Rand Journal of Economics 37, 257-275] present a structural method to estimate search cost distributions. We extend their approach to the case of oligopoly and present a new maximum likelihood method to estimate search costs. We apply our method to a data set of online prices for different computer memory chips. The estimates suggest that the consumer population can be roughly split into two groups which either have quite high or quite low search costs. Search frictions confer a significant amount of market power to the firms: Despite more than 20 firms operating in each of the markets, we estimate price-cost margins to be around 25%. The paper also illustrates how the structural method can be employed to simulate the effects of the introduction of a sales tax.     

The impact of the market transparency unit for fuels on gasoline prices in Germany

Increasing horizontal as well as vertical transparency in oligopolistic markets can be advantageous for consumers, due to reduced search costs. However, market transparency can also affect incentives to deviate from collusive agreements and the punishment by rival firms in the market. Using a panel of 27 European countries, we analyse the impact of increased market transparency via the introduction of a market transparency unit for fuels in Germany. Applying a difference-in-differences approach, we find evidence that both gasoline and diesel prices have increased. While consumers may be better off using a retail price app for fuels, gas stations are also able to compare prices at almost no cost.     

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     

Costly Search, Capacity Constraints, and Bertrand Equilibrium Price Dispersion

This article analyzes the impact of transaction (search) costs and capacity constraints in an almost competitive market with homogeneous firms that compete on price. We characterize conditions under which Nash equilibria with price dispersion exist; in equilibrium, firms play pure strategies in prices and consumers adopt a symmetric mixed search strategy. Price dispersion is possible even though consumers all have the same search cost and valuation for the item and prices charged by all firms are common knowledge.     

Price response,information, and asymmetry of price dispersion

In this study, we examine how differently gasoline prices in 25 regions of Seoul, Korea respond to asymmetric information between retailers and consumers. We estimate the region-specific likelihood that retailers engage in price undercutting under asymmetric information and investigate inter-regional differences. We find that in response to increases in wholesale price, regions with a high likelihood of price undercutting experience intensified gas station price competition while dispersions of price and markups tend to decrease more in response to cost shocks. Understanding the geographical dispersion of retailers’ price responses to information frictions and search intensity is crucial to lowering information barriers across regions and redistributing profit among market participants.     

Price rigidities and institutional variations in markets with posted prices

Summary Standard laboratory posted-offer markets respond slowly and incompletely to demand shocks. In these one-sided markets, where sellers control the setting of prices, very little information is transmitted via the process of exchange. For this reason, traders have trouble distinguishing randomness in their own experience from changes in market fundamentals. This paper reports the results of twelve laboratory markets conducted to assess whether some common variants to standard posted-offer rules can correct the adjustment deficiences. Although discounting, multiple postings and excess demand information all improve performance, we find that response remains poor, and efficiencies low.Support for this research was provided by the National Science Foundation (SBR 9319842 and SBR 9320044), and the University of Virginia Bankard Fund. Data are archived at FTP address: fido.econlab.arizona.edu. We wish to thank Charles Plott and Shyam Sunder for useful comments on an earlier draft of this paper. The usual disclaimer applies.     

TESTING MODELS OF DIFFERENTIATED PRODUCTS MARKETS: CONSOLIDATION IN THE CABLE TV INDUSTRY

Research on differentiated products markets often uses structural demand/supply models to identify firms' marginal costs as product‐level cost data are unavailable. Using unique demand and cost data from cable TV, I evaluate a differentiated products model's ability to identify marginal costs. I find firms systematically price below profit‐maximizing levels, leading to biases in the model's marginal cost estimates. I study the implications for merger simulations and find that these biases compromise estimates of merger‐related cost efficiencies, yet do not prevent these models from generating useful predictions of the price and nonprice effects of mergers.     

实验市场中的价格预期

采用4个变化的口头双向拍卖模拟市场(2个先稳定后通胀,2个先通胀后稳定),本研究发现通胀市场中的预期与理性预期假设吻合良好,同时通货预期不受通胀率的影响。相反稳定市场不支持理性预期模型。结合Williams(1987)的研究结果,本研究提示市场设置是影响稳定市场和通胀市场表现差异的主要原因。     

Inflation, price dispersion, and market structure

In this paper, we use a novel data set containing prices from bazaars, convenience stores, and supermarkets in Istanbul to re-examine the relationship between price dispersion and inflation. Although existing evidence is mixed, we find positive and significant relationships between dispersion, on the one hand, and lagged dispersion and unexpected product-specific inflation on the other. We also find evidence that dispersion is initially decreasing in anticipated aggregate inflation but is eventually increasing. Finally, average price duration and dispersion are lowest in the bazaar. This is intuitive, since menu and search costs should be minimal in that market structure.     

Harassment, corruption and tax policy: A comment on Marjit, Mukherjee and Mukherjee [Eur. J. Political Economy 16 (2000) 75–94]

Our comment on Marjit et al. [Marjit, S., Mukherjee, V., Mukherjee, A., 2000. Harassment, corruption and tax policy. European Journal of Political Economy 16, 75–94.] addresses the equilibrium concept used in the game with imperfect information, Section 4 of the original paper. The solution represented in the original paper does not constitute a perfect Bayesian Nash-equilibrium. We develop an alternative solution of the game given the assumptions made by Marjit et al. [Marjit, S., Mukherjee, V., Mukherjee, A., 2000. Harassment, corruption and tax policy. European Journal of Political Economy 16, 75–94.] and find that the results concerning the optimal amount of over-evaluation of income and the existence of a pooling or separating equilibrium are altered.     

Estimation of hedonic price functions with incomplete information

Existence of persistent price dispersion suggests that some buyers find lower prices through search and information acquisition, while some sellers charge higher prices by gathering information on potential buyers. If buyers are not fully informed of the lowest price available in the market they end up paying a price higher than if they had full information. Similarly, if sellers are not fully informed about the highest price they could charge, they too suffer by receiving a price lower than had they had full information. This paper develops a hedonic price model that incorporates the effects of incomplete information on both sides of the market and obtains estimates of the discrepancies between market prices and buyers’ maximum willingness to pay and sellers’ minimum willingness to accept. Correlates of such price discrepancies are also explored. We apply the technique to a data set constructed from the American Housing Survey, and find that incomplete information has had a significant impact on housing prices.