Competition and market power in option demand markets

We call markets in which intermediaries sell networks of suppliers to consumers who are uncertain about their needs "option demand markets." In these markets, suppliers may grant the intermediaries discounts in order to be admitted to their networks. We derive a measure of each supplier's market power within the network; the measure is based on the additional ex ante expected utility consumers obtain from the supplier's inclusion. We empirically validate the WTP measure by considering managed care purchases of hospital services in the San Diego market. Finally, we present three applications, including an analysis of hospital mergers in San Diego.     

Investment Strategies and Market Structure: An Empirical Analysis of Bank Branching Decisions

This paper analyzes the relationship between the competitive environment faced by depository institutions and the decisions these institutions make regarding the size of their branch networks. Specifically, we consider branches as a sunk investment that potentially increases utility for consumers and examine how local competition and product differentiation affect firms’ decisions regarding whether to make such investments. We account for endogenous market structure using an equilibrium structural model, which corrects for bias caused by correlation in the unobservables associated with market structure and branching activity. We estimate the model using data from 1,882 concentrated rural markets. Our results demonstrate the importance of accounting for market structure and product differentiation, and are consistent with a potential entry-deterring effect of bank branch investments.     

Natural concentration in industrial research collaboration

Empirical work shows that networks of research and development alliances are asymmetric, with a small number of firms involved in the majority of partnerships. This article investigates the welfare‐relevant effects of such concentrated networks in a model of network formation in an oligopolistic market. We find that concentration is a typical characteristic of a socially efficient network when the costs of collaborative activity are significant. Moreover, expanding on prior work relating to strategically stable interfirm networks, we compare the stable and the efficient structures. Our findings suggest that real‐world networks might even exhibit too little concentration.     

Targeting in advertising markets: implications for offline versus online media

We develop a model with many advertisers (products) and many advertising markets (media). Each advertiser sells to a different segment of consumers, and each medium is targeting a different audience. We characterize the competitive equilibrium in the advertising markets and evaluate the implications of targeting. An increase in targeting leads to an increase in the total number of consumer‐product matches, and hence in the social value of advertising. Yet, targeting also increases the concentration of firms advertising in each market. Surprisingly, we then find that the equilibrium price of advertisements is first increasing, then decreasing, in the targeting capacity. We trace out the implications of targeting for competing media. We distinguish offline and online media by their targeting ability: low versus high. As consumers’ relative exposure to online media increases, the revenues of offline media decrease, even though the price of advertising might increase.     

Avoiding market dominance: product compatibility in markets with network effects

As is well recognized, market dominance is a typical outcome in markets with network effects. A firm with a larger installed base offers a more attractive product which induces more consumers to buy its product which produces a yet bigger installed base advantage. Such a setting is investigated here but with the main difference that firms have the option of making their products compatible. When firms have similar installed bases, they make their products compatible in order to expand the market. Nevertheless, random forces could result in one firm having a bigger installed base, in which case the larger firm may make its product incompatible. We find that strategic pricing tends to prevent the installed base differential from expanding to the point that incompatibility occurs. This pricing dynamic is able to neutralize increasing returns and avoid the emergence of market dominance.     

Financial networks with electronic transactions: modelling,analysis and computations

Abstract

Advances in telecommunication networks, and, in particular, the Internet have transformed the economic landscape for financial decision-making. In this paper, we focus on financial networks with electronic transactions and with different tiers of decision-makers and we develop an integrated framework for the modelling, analysis and computation of solutions to such problems. Specifically, we consider an economy consisting of three types of decision-makers: those with sources of funds; intermediary ones, and consumers associated with the financial products at the demand markets. Those with sources of funds can transact with the intermediaries either physically or electronically as well as directly in an electronic manner with the consumers. The intermediaries, in turn, can also transact with the consumers either in a physical or an electronic fashion. We address the behaviour of the decision-makers, identify the network structure of the problem, derive the equilibrium conditions, and establish the variational inequality formulation. In addition, we propose a continuous time adjustment process for the study of the disequilibrium dynamics and prove that the set of stationary points of the resulting projected dynamical system coincides with the set of solutions of the variational inequality. We then utilize variational inequality theory to derive qualitative properties of the equilibrium price and financial flow pattern. Finally, we apply an algorithm for the determination of equilibrium prices and financial flows in several examples.     

Optimal asset allocation for a large number of investment opportunities

This paper introduces a stock‐picking algorithm that can be used to perform an optimal asset allocation for a large number of investment opportunities. The allocation scheme is based upon the idea of causal risk. Instead of referring to the volatility of the assets time series, the stock‐picking algorithm determines the risk exposure of the portfolio by concerning the non‐forecastability of the assets. The underlying expected return forecasts are based on time‐delay recurrent error correction neural networks, which utilize the last model error as an auxiliary input to evaluate their own misspecification. We demonstrate the profitability of our stock‐picking approach by constructing portfolios from 68 different assets of the German stock market. It turns out that our approach is superior to a preset benchmark portfolio. Copyright © 2005 John Wiley & Sons, Ltd.     

Product market advertising and new equity issues

We analyze the interaction between a firm's product market advertising and its corporate financing decisions. We consider a firm that faces asymmetric information in both the product and financial markets and that needs to raise external financing to fund its growth opportunity (new project). Any product market advertising undertaken by the firm is visible to the financial market as well. In equilibrium, the firm uses a combination of product market advertising, equity underpricing, and underfinancing (raising a smaller amount of external capital than the full information optimum) to convey its true product quality and the intrinsic value of its projects to consumers and investors. The following two predictions arise from our theoretical analysis for the relation between product market advertising and equity underpricing around new equity issues. First, firms choose a higher level of product market advertising when they are planning to issue new equity, compared with situations in which they have no immediate plans to do so. Second, product market advertising and equity underpricing are substitutes for a firm issuing new equity. We empirically test the above two predictions and find supporting evidence in the context of firms making initial public offerings and seasoned equity offerings.     

Prominence and consumer search

This article examines the implications of “prominence” in search markets. We model prominence by supposing that the prominent firm will be sampled first by all consumers. If there are no systematic quality differences among firms, we find that the prominent firm will charge a lower price than its less prominent rivals. Making a firm prominent will typically lead to higher industry profit but lower consumer surplus and welfare. The model is extended by introducing heterogeneous product qualities, in which case the firm with the highest‐quality product has the greatest incentive to become prominent, and making it prominent will boost industry profit, consumer surplus, and welfare.     

Non-implementability of Arrow–Debreu equilibria by continuous trading under volatility uncertainty

In diffusion models, a few suitably chosen financial securities allow to complete the market. As a consequence, the efficient allocations of static Arrow–Debreu equilibria can be attained in Radner equilibria by dynamic trading. We show that this celebrated result generically fails if there is Knightian uncertainty about volatility. A Radner equilibrium with the same efficient allocation as in an Arrow–Debreu equilibrium exists if and only if the discounted net trades of the equilibrium allocation display no ambiguity in the mean. This property is violated generically in endowments, and thus Arrow–Debreu equilibrium allocations are generically unattainable by dynamically trading a few long-lived assets.     

Filling in the blanks: network structure and interbank contagion

The network pattern of financial linkages is important in many areas of banking and finance. Yet, bilateral linkages are often unobserved, and maximum entropy serves as the leading method for estimating counterparty exposures. This paper proposes an efficient alternative that combines information-theoretic arguments with economic incentives to produce more realistic interbank networks that preserve important characteristics of the original interbank market. The method loads the most probable links with the largest exposures consistent with the total lending and borrowing of each bank, yielding networks with minimum density. When used in a stress-testing context, the minimum-density solution overestimates contagion, whereas maximum entropy underestimates it. Using the two benchmarks side-by-side defines a useful range that bounds the cost of contagion in the true interbank network when counterparty exposures are unknown.     

Targeted advertising and advertising avoidance

I examine how the increasing ability of firms to target their ads influences market outcomes when consumers have access to advertising‐avoidance tools. Although firms generally benefit from improved targeting, consumers need not. I also show that there may be too little blocking of ads in equilibrium and consider the role of targeted advertising when niche firms compete against mass‐market firms.     

Voluntary Disclosures,Corporate Control,and Investment

We examine the valuation and capital allocation roles of voluntary disclosure when managers have private information regarding the firm’s investment opportunities, but an efficient market for corporate control influences their investment decisions. For managers with long‐term stakes in the firm, the equilibrium disclosure region is two‐tailed: only extreme good news and extreme bad news is disclosed in equilibrium. Moreover, the market’s stock price and investment responses to bad news disclosures are stronger than the responses to good news disclosures, which is consistent with the empirical evidence. We also find that myopic managers are more likely to withhold bad news in good economic times when markets can independently assess expected investment returns.     

基金网络能够提高投资绩效吗？

基金网络在金融市场的信息流动中发挥着重要作用。本文利用基金共同持股关系构建了一个有效的基金网络数据集,以中国资本市场股票型基金2005-2018年季度数据为研究样本,考察基金网络是否以及如何影响投资绩效。结果表明,基金在基金网络中越处于网络中心地位,基金的投资绩效越高。使用基金家族网络作为工具变量缓解内生性偏误后,基金网络仍然对投资绩效具有显著的正向影响。进一步地,本文考察了基金网络影响投资绩效的渠道,结果表明,基金网络主要通过提高基金的选股技能、资产配置技能和管理技能影响投资绩效。最后,本文考察了基金网络对基金市场份额的影响,研究发现基金网络会显著提高基金的市场份额,对基金在市场上的占有率有积极的正向影响。     

The impact of relative information quality of e-commerce assurance seals on Internet purchasing behavior

WebTrust assurance was introduced jointly by the American Institute of Certified Public Accountants (AICPA) and Canadian Institute of Chartered Accountants (CICA) with much fanfare in the late 1990s. Since then, the WebTrust product has not experienced significant market penetration despite providing the highest level of information quality among seals available in the Internet seal market. One reason often given for its poor market penetration is that consumers are unable to differentiate between the information quality of different Internet seals. The purpose of this study is to examine the validity of this explanation. Marketing theory related to consumer risk is used to provide a conceptual foundation for hypotheses related to consumer preferences for Internet seals in general and high information quality seals in particular. The results of the study fail to find consumer interest in a low information quality seal, but did show a strong effect related to preference for a high information quality seal. Unexpectedly, however, these results were not related to buyers' risk propensities.     

Stock Market Efficiency and Economic Efficiency: Is There a Connection?

In a capitalist economy, prices serve to equilibrate supply and demand for goods and services, continually changing to reallocate resources to their most efficient uses. However, secondary stock market prices, often viewed as the most “informationally efficient” prices in the economy, have no direct role in the allocation of equity capital since managers have discretion in determining the level of investment. What is the link between stock price informational efficiency and economic efficiency? We present a model of the stock market in which: (i) managers have discretion in making investments and must be given the right incentives; and (ii) stock market traders may have important information that managers do not have about the value of prospective investment opportunities. In equilibrium, information in stock prices will guide investment decisions because managers will be compensated based on informative stock prices in the future. The stock market indirectly guides investment by transferring two kinds of information: information about investment opportunities and information about managers' past decisions. However, because this role is only indirect, the link between price efficiency and economic efficiency is tenuous. We show that stock price efficiency is not sufficient for economic efficiency by showing that the model may have another equilibrium in which prices are strong-form efficient, but investment decisions are suboptimal. We also suggest that stock market efficiency is not necessary for investment efficiency by considering a banking system that can serve as an alternative institution for the efficient allocation of investment resources.     

Exchange rate regimes, banking and the non-tradable sector

This paper presents a small-open-economy, two-good version of the Diamond and Dybvig model with cash constraints to analyze the implications on banking of different exchange rate regimes and monetary policies. I show that fixed exchange rates with a Central Bank providing liquidity in local currency imply Pareto efficiency, with conditions for a run equilibrium stronger than in the literature. In a flexible exchange rate regime, multiple equilibria may not be eliminated. In particular, for very a expansive monetary policy there exists an equilibrium where a fraction of patient consumers purchases dollars in the interim period, which constitutes a partial currency run. A dollarized banking system without international short-run credit may also implement the efficient allocation under certain conditions.     

Dynamic competition with network externalities: how history matters

We consider dynamic competition among platforms in a market with network externalities. A platform that dominated the market in the previous period becomes “focal” in the current period, in that agents play the equilibrium in which they join the focal platform whenever such equilibrium exists. Yet when faced with higher-quality competition, can a low-quality platform remain focal? In the finite-horizon case, the unique equilibrium is efficient for “patient” platforms; with an infinite time horizon, however, there are multiple equilibria where either the low- or high-quality platform dominates. If qualities are stochastic, the platform with a better average quality wins with a higher probability, even when its realized quality is lower, and this probability increases as platforms become more patient. Hence, social welfare may decline as platforms become more forward looking.     

First‐price auctions with resale and with outcomes robust to bid disclosure

Although there exists a pure separating equilibrium of the two‐bidder first‐price auction with resale when the bids are kept secret, the ratchet effect prevents the existence of such an equilibrium if the bidders are heterogeneous and the bids are fully disclosed. Nevertheless, we construct a behavioral equilibrium under full disclosure that is equivalent to the pure separating equilibrium under no disclosure. Thus, if the bidders follow this equilibrium, the choice of the disclosure regime does not affect the final allocation of the item nor the expected payoffs.     

Oligopolistic markets with sequential search and production cost uncertainty

This article analyzes a sequential search model where firms face identical but stochastic production costs, the realizations of which are unknown to consumers. We characterize a perfect Bayesian equilibrium satisfying a reservation price property and provide a sufficient condition for such an equilibrium to exist. We show that (i) firms set on average higher prices and make larger profits compared to the scenario where consumers observe production costs, (ii) expected prices and consumer welfare can be non‐monotonic in the number of firms, and (iii) the impact of production cost uncertainty vanishes as the number of firms becomes very large.