Strategic segmentation of a market

When competing firms target information towards specific consumers through direct marketing activities, complete segmentation of markets can result. We analyze a two-stage duopoly where, prior to price competition, each firm targets information to specific consumers and only consumers informed by a firm can buy from it. This has the effect of endogenously determining market segments in a model of ‘sales'. In equilibrium, pure local monopoly emerges; firms target and sell to mutually exclusive market segments. When the cost of marketing approaches zero, market shares reflect relative production efficiency (equal shares when firms are symmetric); this may not be the case when marketing cost is high.     

Seller curation in platforms

This article explores why market platforms do not expel low-quality sellers when screening costs are minimal. I model a platform market with consumer search. The presence of low-quality sellers reduces search intensity, softening competition between sellers and increasing the equilibrium market price. The platform admits some low-quality sellers if competition between sellers is intense. Recommending a high-quality seller and this form of search obfuscation are complementary strategies. The low-quality sellers enable the recommended seller to attract many consumers at a high price and the effect of the recommendation is strengthened as low-quality sellers become more adept at imitating high-quality sellers.     

Competitive customer poaching with asymmetric firms

Conditioning the pricing policies on purchase history is proven to generate a cutthroat price competition enhancing consumer surplus. This result typically relies on a framework where competitors are assumed to be symmetric. This paper demonstrates that under significant asymmetries of competing firms, the strong firm trades off current market share for future market share and the weak firm does the opposite. This inter-temporal market sharing agreement generates unidirectional poaching and entails new and distinctive welfare implications. In particular, if consumers are sufficiently myopic, price discrimination softens price competition in relation to uniform pricing, overturning the conclusion of previous studies.     

Auctioning Horizontally Differentiated Items

This paper analyzes competition between two sellers that offer horizontally differentiated items at competing auctions. Three possible outcomes can arise in equilibrium. For substantially differentiated items the monopoly reserve prices form an equilibrium, and the market is not entirely covered. When products become closer substitutes, a non-empty interval of types becomes valuable to both sellers. When transport costs are low, and virtual valuations are high, sellers compete for these bidders and set their reserve prices below the valuation of the marginal bidder. In equilibrium all types enjoy participation rents. For intermediate levels of transport costs it is not worth competing for runaway bidders. In this case, there is a continuum of equilibria. In each equilibrium sellers adjust their reserve prices so that the marginal bidder gets no rents.     

When can auctions maximize post-auction welfare?

I study auctions in which firms bid for licenses that reduce their marginal costs in a post-auction downstream market. When there are three or more firms, I show that the Vickrey–Clarke–Groves (VCG) auction maximizes consumer surplus in dominant strategies if and only if it maximizes producer surplus in dominant strategies. With two firms, the effect on consumer surplus is ambiguous. When the VCG auction does not maximize consumer surplus, I show that consumer surplus can be maximized by adding caps, i.e., restricting the number of licenses a bidder can win. This might lower producer surplus.     

基于商品质量偏好的双边市场定价策略分析

本文研究了双边市场一方用户群体提供商品或服务的质量在垄断市场情形和单归属（接入）寡头垄断市场情形下对双边市场平台定价问题。研究结果表明：在寡头垄断情形下,消费方和厂商的接入费用和其本身对质量的敏感程度及质量成本系数相关,平台具有鼓励符合条件的用户接入平台的动机。在单归属的寡头垄断情形下,平台之间的厂商无质量差异时,平台倾向于定高价以获取由商品质量引起的双边市场的剩余价值,而消费者和厂商均没有提高商品质量的要求和激励;在寡头平台之间的商品或服务质量差距小,质量信息不透明时,优势平台会随着质量差距扩大而提高厂商的接入费用,其消费者的数量也会增多;若质量信息透明,质量劣势平台为了保持市场份额,其价格与另一寡头平台的消费者市场的接入费用差距与质量差距成正比,而在厂商市场的接入费用差距与质量差距成反比。     

Oligopoly under incomplete information: On the welfare effects of price discrimination

We study competition by firms that simultaneously post (potentially nonlinear) tariffs to consumers who are privately informed about their tastes. Market power stems from informational frictions, in that consumers are heterogeneously informed about firms’ offers. In the absence of regulation, all firms offer quantity discounts. As a result, relative to Bertrand pricing, imperfect competition benefits disproportionately more consumers whose willingness to pay is high, rather than low. Regulation imposing linear pricing hurts the former but benefits the latter consumers. While consumer surplus increases, firms’ profits decrease, enough to drive down utilitarian welfare. By contrast, improvements in market transparency increase utilitarian welfare, and achieve similar gains on consumer surplus as imposing linear pricing, although with limited distributive impact. On normative grounds, our analysis suggests that banning price discrimination is warranted only if its distributive benefits have a weight on the societal objective.     

Personalized pricing and advertising: Who are the winners?

This paper investigates who wins and who loses when firms depart from a mass advertising/uniform pricing strategy (benchmark model) to a targeted advertising/price discrimination one. Considering a duopoly market in which firms simultaneously compete in prices and advertising decisions, we examine the competitive and welfare effects of personalized pricing with targeted advertising by comparing equilibrium outcomes under customized advertising/ pricing decisions to the results arising under mass advertising and uniform pricing. We show that, when both firms compete in both market segments, all segment consumers are expected to pay higher average prices under the personalized advertising/pricing strategy. We also show that, in the context of our simultaneous game, targeted advertising with price discrimination might boost firms’ profits in comparison to the case of mass advertising and uniform prices. The overall welfare effects of the personalized strategy are ambiguous. However, even when the personalized strategy boosts overall welfare, consumers might all be worse-off. Thus the paper gives support to concerns that have been raised regarding the firms’ ability to adopt personalized strategies to boost profits at the expense of consumers.     

Mechanism choice and the buy-it-now auction: A structural model of competing buyers and sellers

A striking feature of many online sales platforms is the coexistence of multiple sales mechanisms. Items on eBay, for instance, are frequently offered through auctions, posted prices, and buy-it-now auctions. In this article, I study how this mechanism multiplicity influences the welfare of buyers and sellers. I specify and estimate a structural model of mechanism choice in online markets, in which I consider both sides of the market: On the demand side, buyers' choices among available listings are equilibrium outcomes of an entry game. On the supply side, sellers make equilibrium decisions when choosing sales mechanisms and prices. I estimate this model using data from sales of baseball tickets on eBay and calculate consumer and seller rents in three markets: the actual market with all three sales mechanisms and two counterfactual markets with auctions and fixed prices or only fixed-price listings, respectively. I find that the addition of auctions to fixed-price markets hurts sellers and risk-averse buyers but benefits risk-neutral buyers. Additionally, the consumer surplus increases when buy-it-now auctions are offered but the seller surplus is reduced further. I discuss the intuition for the cause of this result.     

Rationalizability and efficiency in an asymmetric Cournot oligopoly

This paper studies rationalizability in a linear asymmetric Cournot oligopoly with a unique Nash equilibrium. It shows that mergers favor uniqueness of the rationalizable outcome. When one requires uniqueness of the rationalizable outcome maximization of consumers' surplus may involve a symmetric oligopoly with few firms. We interpret uniqueness of the rationalizable outcome as favoring a dampening of strategic ‘coordination’ uncertainty. An illustration to the merger between Delta Air Lines and Northwest shows that a reallocation of 1% of market share from a small carrier to a larger one has implied a lower production volatility over time, yielding a 1.5% decrease in the coefficient of variation of number of passengers.     

COSTLY BUYER SEARCH IN LABORATORY MARKETS WITH SELLER ADVERTISING*

In this experiment, sellers simultaneously choose prices and advertising strategies. Buyers either purchase at an advertised price or search sequentially for other prices. In the unique symmetric equilibrium, sellers charge a high unadvertised price or advertise a price chosen from a lower interval. Increases in search or advertising costs raise equilibrium prices and affect equilibrium advertising intensity. Empirical results are consistent with most comparative static predictions. Sellers, however, price much lower and advertise more intensely than predicted. Consequently, market outcomes more closely resemble a perfect information, Bertrand‐like equilibrium than the imperfect information, mixed strategy equilibrium with significant seller market power.     

Pricing with customer recognition

This article studies the dynamic effects of behaviour-based price discrimination and customer recognition in a duopolistic market where the distribution of consumers' preferences is discrete. Consumers are myopic and firms are forward looking. In the static and first-period equilibrium firms choose prices with mixed strategies. When price discrimination is allowed, forward-looking firms have an incentive to avoid customer recognition, thus the probability that both will have positive first-period sales decreases as they become more patient. Furthermore, an asymmetric equilibrium sometimes exists, yielding a 100–0 division of the first-period sales. As a whole, price discrimination is bad for profits but good for consumer surplus and welfare.     

Segmentation, advertising and prices

This paper explores the implications of market segmentation on firm competitiveness. In contrast to earlier work, here market segmentation is minimal in the sense that it is based on consumer attributes that are completely unrelated to tastes. We show that when the market is comprised by two consumer segments and when there is sufficient variation in the per-consumer costs firms need to incur to access the different consumer populations, then firms obtain positive profits in symmetric equilibrium. Otherwise, the equilibrium is characterized by zero profits. As a result, a minimal form of market segmentation combined with advertising cost asymmetries across consumer segments give firms an opportunity to generate positive rents in an otherwise Bertrand-like environment.     

Optimal Concentration and Deadweight Losses in Canadian Manufacturing

When economies of scale are impontant, there may be too many firms in a market to effectively exploit these scale economies. Although more firms imply reduced market power, this may not offset the adverse impact of higher unit cost. We explore this trade-off by estimating for 107 Canadian industries optimal concentration, this being the concentration that maximizes, for given firm conduct, producers and consumers' surplus. We then calculate deadweight losses as the difference between total surplus at optimal concentration and total surplus at current concentration levels. Among the conclusions are that the majority of industries have concentration that is too low.     

The effects of personal information on competition: Consumer privacy and partial price discrimination

This article studies the effects of consumer information on the intensity of competition. In a two dimensional duopoly model of horizontal product differentiation, firms use consumer information to price discriminate. I contrast a full privacy and a no privacy benchmark with intermediate regimes in which the firms can profile consumers only partially. I show that with partial privacy firms are always better-off with price discrimination: the relationship between information and profits is hump-shaped. In particular, competing firms prefer to target consumers with partial but asymmetric information about preferences. Instead, consumers prefer either no or full privacy in aggregate, but the effects of information on individual surplus are ambiguous: there are always winners and losers. Finally, I study the information acquisition incentives of the firms when there is an external data seller. When this upstream data broker holds partially informative data, an exclusive allocation arises. Instead, when data is fully informative, each competitor acquires consumer data but on a different dimension. These findings are relevant for the strategic decisions of firms active in digital markets and contribute to the policy debate surrounding privacy, exclusive access to data and competition.     

Nonsequential search equilibrium with search cost heterogeneity

We generalize the model of Burdett and Judd (1983) to the case where an arbitrary finite number of firms sells a homogeneous good to buyers who have heterogeneous search costs. We show that a price dispersed symmetric Nash equilibrium always exists. Numerical results show that the behavior of prices and consumer surplus with respect to the number of firms hinges upon the nature of search cost dispersion: when search costs are relatively concentrated, entry of firms leads to lower average prices and greater consumer surplus; however, for relatively dispersed search costs, the mean price goes up and consumer surplus may decrease with the number of firms.     

Platform Price Parity Clauses and Consumer Obfuscation*

Several antitrust authorities have investigated platform price parity clauses around the world. I analyze the impact of these clauses when platforms design a search environment for sellers and buyers to interact. In a model where platforms choose the unit search cost faced by consumers, I show when platforms can profitably obfuscate consumers through high search costs. Then, I show that price parity clauses, when exogenously given, can increase or reduce obfuscation, prices, and consumer surplus. Finally, when price parity clauses are endogenous, they are only observed in equilibrium if they hurt consumers.     

Curbing obfuscation: Empower consumers or regulate firms?

This paper develops a market model where consumers refrain from buying products that they are unable to understand and a firm can influence the probability of a consumer understanding its offer. In equilibrium, firms artificially increase product complexity, and firms that offer more transparent products choose on average higher prices. We study two sets of public policies. We show that consumer side policies may have the unintended consequence of encouraging obfuscation while firm side policies are always effective in curbing obfuscation. Interestingly, a consumer side policy can even harm consumers when it protects consumers so much that it greatly increases the marginal effectiveness of obfuscation. Policies on both sides can either increase or decrease social welfare depending on the marginal effectiveness and the marginal cost of obfuscation. Our main insights hold in both asymmetric and symmetric obfuscation equilibria.     

Third-Degree Price Discrimination in Oligopoly when Markets are Covered*

We analyze oligopolistic third-degree price discrimination relative to uniform pricing when markets are covered. Pricing equilibria are critically determined by supply-side features such as the number of firms and their marginal cost differences. It follows that each firm's Lerner index under uniform pricing is equal to the weighted harmonic mean of the firm's relative margins under discriminatory pricing. Uniform pricing then lowers average prices and raises consumer surplus. We can calculate the gain in consumer surplus and loss in firms' profits from uniform pricing based only on the market data of the discriminatory equilibrium (i.e., prices and quantities).     

Group Consumption and Product Diversity: The Case of Smoking Bans

I study product diversity in the presence of search costs and groups of consumers. Groups with heterogeneous tastes create a leverage effect on competition: a large majority of firms may end up offering a product that corresponds to the taste of the minority. I illustrate this idea with smoking bans in bars and restaurants. When the first nonsmoking restaurants opened, there were few of them with little competition and high market power on nonsmokers. By extracting a large surplus from nonsmokers, nonsmoking restaurants became unattractive to other groups, while smoking restaurants were plenty and competitive, attracting both smokers and mixed groups.