equilibrium price dispersion with heterogeneous searchers abstract firms simultaneously set prices in a homogeneous product market where uninformed consumers search for price information some uninformed consumers are local searchers who visit only one seller whereas others search sequentially with an optimal reservation price equilibrium prices may follow a mixture distribution with clusters of high and low prices separated by a zero density gap when the exogenous reservation price of local searchers depart from that of the optimizing sequential searchers by a relatively small amount the presence of local searchers either has no effect on market outcomes or benefits all consumers a reduction in search cost sometimes leads to higher equilibrium prices

frictionless commerce a comparison of internet and conventional retailers there have been many claims that the internet represents a new nearly frictionless market our research empirically analyzes the characteristics of the internet as a channel for two categories of homogeneous products books and cds using a data set of over 8 500 price observations collected over a period of 15 months we compare pricing behavior at 41 internet and conventional retail outlets we find that prices on the internet are 9 16 lower than prices in conventional outlets depending on whether taxes shipping and shopping costs are included in the price additionally we find that internet retailers price adjustments over time are up to 100 times smaller than conventional retailers price adjustments presumably reflecting lower menu costs in internet channels we also find that levels of price dispersion depend importantly on the measures employed when we compare the prices posted by different internet retailers we find substantial dispersion internet retailer prices differ by an average of 33 for books and 25 for cds however when we weight these prices by proxies for market share we find dispersion is lower in internet channels than in conventional channels reflecting the dominance of certain heavily branded retailers we conclude that while there is lower friction in many dimensions of internet competition branding awareness and trust remain important sources of heterogeneity among internet retailers

competition and the number of firms in a market are duopolies more competitive than atomistic markets this paper uses a variant of the standard search model to examine market equilibrium and the consequences for market equilibrium of an increase in the number of firms if marginal search costs increase with the number of searches then the demand curve facing any firm will be kinked with the elasticity of demand with respect to price decreases being less than with respect to price increases prices may not change in response to changes in marginal costs as the number of firms increases the maximum price that is consistent with equilibrium increases to the monopoly price but the minimum price decreases on the other hand if marginal search costs decrease with the number of searches equilibrium if it exists is characterized by a

expanding demand through price advertisement abstract retail stores frequently advertise prices when consumer search is costly advertising low prices expands the number of consumers who visit and buy we show that this demand enhancement may offset a retailer s loss in margins from the low price making advertisement desirable we further show that a multi product monopolist may choose to advertise low prices only for select products even when advertised and non advertised products are substitutes for duopolist retailers at a common location an equilibrium exists in which for some range of advertising costs one store advertises and the other free rides on its competitor

strategic price complexity in retail financial markets abstract there is mounting empirical evidence to suggest that the law of one price is violated in retail financial markets there is significant price dispersion even when products are homogeneous also despite the large number of firms in the market prices remain above marginal cost and may even rise as more firms enter in a non cooperative oligopoly pricing model i show that these anomalies arise when firms add complexity to their price structures complexity increases the market power of the firms because it prevents some consumers from becoming knowledgeable about prices in the market in the model as competition increases firms tend to add more complexity to their prices as a best response rather than make their disclosures more transparent because this may substantially decrease consumer surplus in these markets such practices have important welfare implications

the market for quacks a group of n quacks plays a price competition game facing a continuum of patients who recover with probability whether or not they acquire a quack s treatment if patients chose rationally the market would be inactive i assume however that patients choose according to a boundedly rational procedure which re ects anecdotal reasoning this element of bounded rationality has signi cant

a search cost model of obfuscation this article develops models in which obfuscation is individually rational for oligopolistic firms firms sell a homogeneous good to rational consumers who incur search costs to learn prices search costs are endogenized by allowing obfuscation firms have an unobservable action that increases the time needed to learn their price one model involves search costs convex in shopping time we show that slight convexity can dramatically alter the equilibrium price distribution a second model examines an informational linkage between current and future search costs consumers are uncertain about a component of search costs here a signal jamming mechanism can lead to equilibrium obfuscation

bargaining and waning commitments this paper presents a non cooperative two agent two period complete information bargaining model that introduces gradual concession as observed for example in labor negotiations the capacity of concession may affect the agents payoffs in a non monotonic way since its change may cause the timing of agreement to change d 2006 elsevier b v all rights reserved

instant option betas an investor considering the addition of options to his investment portfolio must consider the effect an option will have on portfolio risk the eta of an option at any point in time can be calculated from the beta of its underlying stock and the option s risk elasticity a measure of the percentage change in the value of the option for a small percentage change in the value of the underlying stock an option s beta will change in a predictable fashion with changes in the underlying stock s price and variance rate the option s exercise price and time to expiration and the risk free interest rate a call option s beta will decrease with increasing stock price and exercise price and increase with an increasing risk free rate its sensitivity to variance and time to expiration will depend on the stock price to exercise price ratio nomograms provide a quick and easy way to estimate option betas from these readily observable underlying parameters option betas will also change often drastically with the passage of time graphs indicate that in general call betas will increase as time to expiration increases the ultimate impact will depend however on the parameters of the contract and on changes in the underlying stock s price

price directed consumer search abstract we extend stahl s 1989 model to a setting with differentiated products to study the effects of price directed consumer search consumers engage in costly search to find out whether products meet their needs consumer search is directed by prices when they are observable before search in contrast to the case in which prices are discovered only after search where search is naturally random the equilibrium under price directed search differs substantially from that under random search despite certain similarities we show that as search costs decrease sales become more likely and firms earn higher expected profits under price directed search whereas the opposite holds under random search moreover compared with random search under price directed search firms expected profits are always lower but consumer surplus and total welfare are higher provided that the search cost is sufficiently small

talking searching and pricing this paper studies a consumers search model with word of mouth communication firms market a homogeneous product and choose prices consumers obtain price information in two ways they can search on their own and they can talk to other consumers in the basic model word of mouth communication is exogenous and the focus is on how the level of word of mouth communication shapes market equilibrium outcomes when search costs are low an intensification in word of mouth communication decreases firms competition the opposite holds when search costs are high the model is then extended to allow for strategic word of mouth communication market equilibria with word of mouth communication have the feature that some consumers acquire information personally while other consumers obtain their information by networking with others a decrease in the costs of word of mouth communication relatively to the costs of searching reduces the fraction of consumers who acquire information personally consequently it decreases firms competition

consumer search and dynamic price dispersion an application to gasoline markets this article studies the role of imperfect information in explaining price dispersion we use a new panel data set on the u s retail gasoline industry and propose a new test of temporal price dispersion to establish the importance of consumer search we show that price rankings vary significantly over time however they are more stable among stations at the same street intersection weestablishtheequilibriumrelationshipsbetweenpricedispersionandkeyvariables from consumer search models price dispersion increases with the number of firms in the market decreases with the production cost and increases with search costs

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

an experimental study of price dispersion in an optimal search model with advertising abstract this paper reports a laboratory experiment to study pricing and advertising behavior with costly buyer search sellers simultaneously post prices and may incur a cost to advertise this price in the unique symmetric equilibrium sellers either charge a high unadvertised price or randomize in an interval of lower advertised prices increases in search or advertising costs raise equilibrium prices and equilibrium advertising intensity decreases with lower search costs and higher advertising costs our experimental results support these comparative static predictions and sellers also post high unadvertised prices as predicted in all treatments however sellers advertise more intensely than in equilibrium

an equilibrium model of search unemployment this paper develops a simple general equilibrium model with sequential search in which a nondegenerate wage offer distribution is endogenously determined we use this model to analyze the comparati

estimation of search frictions in the british electricity market this paper studies consumer search and pricing behaviour in the british domestic electricity market following its opening to competition in 1999 we develop a sequential search model in which an incumbent and an entrant group compete for consumers who nd it costly to obtain information on prices other than from their current supplier we use a large data set on prices and input costs to structurally estimate the model our estimates indicate that consumer search costs must be relatively high in order to rationalize observed pricing patterns we confront our estimates with observed switching behaviour and

mixed strategy trade equilibria textabstractconsiders the hybrid situation where some customers care only about the price while others have a brand preference or care about product characteristics

lessons about markets from the internet many of us have grown used to tired of and finally downright skeptical of claims of the transformative powers of the internet it was to usher in the new economy but we seem mostly to have the old it would transform retail but toys r us has outlasted etoys frictionless commerce would be the norm but plenty of friction still exists the internet was also claimed to require a whole new economics with all new laws while this too was very far from the truth existing theories have mostly done quite well the internet has had a substantial effect on economic thought in this paper we discuss some ways in which the internet has affected how economists think about markets

a model of sales with differentiated and homogeneous goods abstract this paper extends the classical model of sales varian 1980 rosenthal 1980 by adding product differentiation instead of uninformed i e loyal customers our setting features variety seekers these consumers regard the products as imperfect substitutes as in the original model the firms also serve bargain seekers who buy the cheapest product the discontinuous demand structure precludes any pure strategy equilibria we characterize the symmetric mixed strategy equilibrium of the modified game in contrast to the original model the upper bound on prices and the equilibrium expected profits are decreasing in the mass of bargain seekers

price dispersion in the lab and on the internet theory and evidence price dispersion is ubiquitous in settings that closely approximate textbook bertrand competition we show that only a little bounded rationality among sellers is needed to rationalize such dispersion a variety of statistical tests based on datasets from two independent laboratory experiments and structural estimates of the parameters of our models suggest that bounded rationality based theories of price dispersion organize the data remarkably well evidence is also presented to suggest that the models are consistent with data from a leading internet price comparison site

optimal firm behavior with consumer social image concerns and asymmetric information abstract this paper explores how consumers belief dependent social image concerns can affect firm strategic choices in a product market setting we consider a theoretical framework with incomplete information where a profit maximizing monopolist sets a price for its product taking into account that consumers care about the belief that others hold about the product s popularity throughout our analysis we highlight the close connection between our dynamic psychological game and the literature on network effects we show in particular that belief dependent social image concerns generate equilibrium price distortions that do not arise in a network effect setting and we explore the implications for consumer demand and firm profits

a model of price promotions with consumer search this paper presents a price discrimination model of price promotions the distinguishing feature of our model is the explicit distinction between regular and promotional prices regular prices are chosen first then promotional prices further while regular prices are always available to everyone promotional prices are only available when offered and only to those who search for them we show that even a monopolist will offer random promotions under these circumstances furthermore as search costs increase the frequency and depth of promotions increase with competition for the promotion oriented consumers the seller becomes more aggressive in his promotional policies even more so as search costs increase the high reservation price consumers however end up worse off with competition

number of sellers average prices and price dispersion abstract a variety of models provide differing predictions regarding the effect of an increase in the number of competitors in a market seller density on prices and price dispersion we review different approaches to generating equilibrium price dispersion and then empirically estimate the relationship between seller density average product price and price dispersion in the retail gasoline industry using four unique gasoline price data sets controlling for station level characteristics we find that an increase in station density consistently decreases both price levels and price dispersion across four geographical areas

bargaining with imperfect commitment abstract we study the effect of imperfect commitment in noncooperative two person bargaining games by establishing the reputation for being stubborn a player sometimes commits to her initial demand becoming unable to change her demands or to accept an inferior offer from her opponent when the probability of being stubborn is small the set of equilibria is shown to be small and agreement may be reached immediately despite the possibility of stubbornness a player has greater bargaining power when she is more patient and or is more likely to be stubborn journal of economic literature classification number c78

consumer search with asymmetric price sampling we explore asymmetries in the way consumers sample prices in a simple sequential search framework in equilibrium the price distribution of a firm catering to more local consumers first order stochastically dominates that of its rival prices rise in the degree of asymmetry

it takes two to tango equilibria in a model of sales we show that the varian model of sales with more than two firms has two types of equilibria a unique symmetric equilibrium and a continuum of asymmetric equilibria in contrast the 2 firm game has a unique equilibrium that is symmetric for the n firm case the asymmetric equilibria imply mixed strategies that can be ranked by first order stochastic dominance this enables one to rule out asymmetric equilibria on economic grounds by constructing a metagame in which both firms and consumers are players the unique subgame perfect equilibrium of this metagame is symmetric

the advertising mix for a search good we extend the persuasion game to bring it squarely into the economics of advertising we model advertising as exciting consumer interest into learning more about the product and determine a firm s equilibrium choice of advertising content over quality information price information and horizontal match information equilibrium is unique whenever advertising is necessary the outcome is a separating equilibrium with quality unravelling lower quality firms need to provide more information for a given quality level as a function of consumer visit costs first quality information is disclosed then price information and then horizontal product information are added to the advertising mix some suggestive evidence is provided from airline ads in newspapers this paper was accepted by j miguel villas boas marketing

oligopolistic pricing with heterogeneous consumer search abstract a finite number of identical stores sell a homogeneous good to consumers with heterogeneous search costs who search sequentially with perfect recall and without replacement consumers search rules are optimal with respect to the stores pricing strategies and consumers must visit a store to obtain information about its actual price a symmetric nash equilibrium sne always exists the model exhibits a variety of equilibrium behaviors between monopoly pricing and marginal cost pricing the competitiveness of a market depends crucially on the shape of the search cost distribution moreso than on the number of competing firms

equilibrium price distributions equilibrium price distributions for a homogeneous product consistent with individual incentives are investigated they arise in informationally imperfect markets in which the only primitive datum is the distribution of search costs it is shown that single multi and continuous price distributions are all viable long run phenomena depending on the nature of search costs a method for computing equilibrium price distributions is also provided jevons law of one price has long been an accepted dictum in economic theory in a classroom presentation it still serves sometimes implicitly as a major premise in many micro models of market interaction much of the descriptive theory as well as welfare analysis hinges on this assumption yet one s day to day experience reveals that price differentials are a viable phenomenon and that looking for lower prices may very well be a rewarding activity the prospects of eventually hitting a bargain and the resulting price reduction would more than compensate for the cost incurred during the search process moreover the existence of price dispersions appear to be an empirically stable phenomenon snapshots of markets for relatively homogeneous products reveal substantial and recurring price differentials stigler 1961 and pratt wise and zeckhauser 1979 for example report some evidence supporting this claim an important article by stigler 1961 focused economists attention on the crucial role played by the informational structure of markets it gave rise to the study of the

revocable commitment and sequential bargaining in this paper the author presents a noncompetitive bargaining model which unifies the two well known but distinct bargaining games due to j nash 1953 and a rubinstein 1982 moreover the author explores the robustness of the equilibrium set of these two bargaining games to a particular kind of perturbation in the commitment structure of the underlying extensive forms from a different perspective and interpretation of the model the author examines and studies the relationship between the equilibrium commitment levels and the costs to the bargainers of revoking their respective commitments copyright 1992 by royal economic society

advertising for consideration abstract we analyze markets where firms competing on price advertise to increase the probability of entering consumers consideration sets we find that moderately costly advertising allows firms to raise prices and possibly profits by reducing the fraction of price conscious consumers and by segmenting the market according to whether or not consumers consider the lower priced firm however when the cost of advertising is sufficiently low advertising leads to a prisoners dilemma that adversely impacts profits without affecting expected prices

oligopolistic pricing with sequential consumer search n identical stores compete by choosing prices for a homogeneous good with constant marginal costs consumers search sequentially with perfect recall for the lowest price one class of consumers called shoppers have zero search costs while all other consumers have a positive search cost c there is a unique symmetric nash equilibrium price distribution with the property that it changes smoothly from marginal cost pricing when all consumers are shoppers and or c 0 and monopoly pricing when no consumers are shoppers remarkably as the number of stores increases the nash equilibrium becomes more monopolistic copyright 1989 by american economic association

the rationale behind interfirm tender offers information or synergy this paper investigates the rationale behind interlirm tender offers by examining the returns realized by the stockholders of lirms that were the targets of unsuccessful tender offers and lirms that have made unsuccessful offers our results suggest that the permanent positive revaluation of the unsuccessful target shares documented by dodd and ruback 1977 and bradley 1980 is due primarily to the emergence of and or the anticipation of another bid that would ultimately result in the transfer of control of the target resources we also find that the rejection of a tender offer has differential effects on the share prices of the unsuccessful bidding firms depending upon whether the tender offer process results in a change in the control of target resources on the basis of these results we conclude that acquisitions via tender offers are attempts by bidding firms to exploit potential synergies not simply superior information regarding the true value of the target resources

on corporate governance a study of proxy contests abstract this paper examines a sample of firms experiencing proxy contests for seats on their board of directors dissident shareholders usually fail to obtain a majority of board seats nevertheless they capture some seats via mechanisms such as cumulative voting in over half of the sample contests regardless of proxy contest outcome positive and statistically significant share price performance is associated with the contest that finding is predicted by the standard economic analysis of proxy contests in which the challenges benefit shareholders by improving corporate performance the finding runs counter to the claim of berle 1962 that the economists view of proxy contests is a wholly imaginary picture a portion of the positive share price changes taking place in the early stages of some proxy contests is not permanent however and as suggested by manne 1962 is at least partially attributable to temporary increases in the market value of the vote attached to corporate shares

a search model where consumers choose quantity based on expected price i describe a price game in which consumers face search costs and base their quantity decision on the expected price because of search costs the choice of the firm they will buy from is described by a random process i show that the expected equilibrium price is above the monopoly price this result does not change if demand comes from a small share of perfectly informed consumers with zero search costs

non reservation price equilibrium and search without priors we analyse a model of oligopolistic competition in which consumers search without priors consumers do not have prior beliefs about the distribution of prices charged by firms and thus try to use a robust search procedure we show that the optimal stopping rule is stochastic and that for any distribution of search costs there is a unique market equilibrium which is characterised by price dispersion although listed prices approach the monopoly price as the number of firms increases the effective price paid by consumers does not depend on the number of firms

a bargaining model based on the commitment tactic abstract this paper studies a one shot simultaneous move bargaining game each bargainer makes a partial commitment a share of the unit size cake that she would like to get which can later be revoked at some cost to the player the payoffs are defined in part by the nash bargaining solution where the feasible utility set is affected by the players partial commitments under certain assumptions on the two cost of revoking functions we establish that the model has a unique nash equilibrium it is shown that a player s equilibrium share of the cake is strictly increasing in her marginal cost of revoking a partial commitment an application of our model selects a unique equilibrium in nash s demand game journal of economic literature classification number c78

the pricing effects of interfirm cash tender offers the tools provided by option pricing theory are used to examine the wealth effects of interfirm cash tender offers the analysis provides evidence consistent with the synergy theory of corporate takeovers and has implications concerning the economic effects of regulations of cash tender offers the analysis further suggests that the market prices information uncertainty in a manner not captured by the standard capital asset pricing model the study introduces a technique for unbundling the prices of a primary asset and a contingent claim when only the prices of the combination are observed academics the business community and government regulators have focused considerable attention on corporate takeovers in this paper we extend the literature on takeovers in two ways first we utilize the tools provided by optionpricing theory to examine the wealth effects of interfirm cash tender offers this analysis provides some new evidence on the possible motivations for corporate takeovers second we examine the pricing of a target firm s common stock following an interfirm cash tender offer this examination suggests that the market prices information uncertainty in a manner not captured by the standard capital asset pricing model capm in addition to providing evidence on tender offers and asset pricing the study also introduces a technique for unbundling the prices of a primary asset and a contingent claim when only the prices of the combination are observed this technique has the potential to be used in other applications previous researchers have documented substantial wealth gains for target

prices and heterogeneous search costs we study price formation in a model of consumer search for differentiated products in which consumers have heterogeneous search costs we provide conditions under which a pure strategy symmetric nash equilibrium exists and is unique search costs affect two margins the intensive search margin or search intensity and the extensive search margin or the decision to search rather than to not search at all these two margins affect the elasticity of demand in opposite directions and whether lower search costs result in higher or lower prices depends on the properties of the search cost density

price competition and endogenous valuation in search advertising abstract this article studies how to endogenously assess the value of a superior advertising position in the price competition and examines the resulting location competition outcomes and price dispersion patterns the authors consider a game theoretic model in which firms compete for advertising positions and then compete in price for customers in a product market firms differ in their competence and positions are differentiated in their prominence which reflects consumers online search behavior they find that when endogenously evaluated within the product market competition a prominent advertising position might not always be desirable for a firm with competitive advantage even if it is cost free the profitability of a prominent advertising position depends on the trade off between the extra demand from winning the position and the higher equilibrium prices when the weaker competitor wins it furthermore the authors show that the bidding outcome might not align with the relative competitive s

competition and price discrimination evidence from the parking garage industry we study the relationship between competition and price discrimination through an empirical examination of hourly price schedules in the parking garage industry we find that the degree of price schedule curvature decreases with competition implying a greater proportionate drop in low end prices than in high end prices when competition intensifies our findings suggest that competition constrains a firm s capacity to exercise price discrimination confirming the classic textbook theory we also offer possible explanations for our findings including a search cost explanation for which we find some support in the data

delay in multilateral bargaining under complete information abstract this paper analyzes a complete information infinite horizon multilateral bargaining model in which one player bargains with each of the other players one at a time and binding cash offer contracts are used to govern transactions under a weak stationarity condition on equilibrium strategies we characterize the set of equilibria for the game we show that when players are sufficiently patient significant delay in reaching agreements may emerge and this delay can become longer quickly as the number of involved parties rises indeed when the number of bargainers is large perpetual disagreement can occur in equilibrium journal of economic literature classification numbers c78 d23 d62

a simple model of price dispersion abstract this article considers a simple stock flow matching model with fully informed market participants unlike the standard matching literature prices are assumed to be set ex ante when sellers pre commit themselves to sell their products at an advertised price the unique equilibrium is characterized by price dispersion due to the idiosyncratic match payoffs in a marketplace with full information this provides new insights into the price dispersion literature which instead commonly assumes that buyers are not perfectly informed and engage in a costly search

a reexamination of analysts earnings forecasts for takeover targets abstract we examine analysts earnings forecasts for a sample of takeover targets and document that the announcement month forecasts are systematically revised upward supporting the hypothesis that a takeover announcement conveys favorable information about the target firm in addition we find that abnormal forecast revisions of future stand alone earnings are significantly greater for targets with low tobin s q ratios relative to targets with high q ratios lending further support to the information hypothesis finally we provide evidence that managerial resistance to the takeover does not destroy value our results are in direct contrast to pound 1988

strategic pricing consumer search and the number of firms discover prices there are three distinct price dispersed equilibria characterized by low moderate and high search intensity the effects of an increase in the number of firms on search behaviour expected prices price dispersion and welfare are sensitive i to the equilibrium consumers search intensity and ii to the status quo number of firms for instance when consumers search with low intensity an increase in the number of firms reduces search does not affect expected price leads to greater price dispersion and reduces welfare in contrast when consumers search with high intensity increased competition results in more search and lower prices when the number of competitors in the market is low to begin with but in less search and higher prices when the number of competitors is large duopoly yields identical expected price and price dispersion but higher welfare than an infinite number of firms a question that has received much attention in economic theory is how the number of competitors and market outcomes are related despite the existence of work showing the contrary see e g satterthwaite 1979 rosenthal 1980 the prediction that emerges from a market where firms interact in a cournot fashion has come to dominate economic thought namely that an increase in the number of competitors leads to larger aggregate production lower market price and improved market performance measured in terms of some social welfare criterion ruffin 1971 this paper challenges the generality of this belief by presenting an oligopoly model with consumer search where the equilibrium expected price may be constant increasing or nonmonotonic in the number of firms we present an economy with two types of consumers consumers who search for prices at no cost fully informed and consumers who must pay a fixed search cost for each price quotation they observe less informed 1 all buyers have the same willingness to pay for the good and buy either a single unit or nothing at all on the supply side of the market there are n firms producing a homogeneous good at constant marginal cost we analyse a one shot simultaneous move game firms set prices and consumers decide how many prices to search for at the same moment in time our model is essentially an oligopolistic version of burdett and judd 1983 where some consumers search costlessly in this model consumers search using a fixed sample size search strategy i e they choose the number of prices to observe before receiving any offer nonsequential search is appealing when consumers find it more advantageous to gather price information quickly morgan and manning 1985 this occurs when the search outcome is observed with delay and delay is costly for instance an mba graduate looking for a job 1 the presence in the model of consumers who search costlessly captures the fact that some people have a

inattentive consumers and product quality this paper studies a model in which some consumers shop on the basis of price alone without attention to potential differences in product quality a firm may offer a low quality product to exploit these inattentive consumers in the unique symmetric equilibrium of the model firms choose prices with mixed strategies similarly to varian 1980 in which some consumers purchase from a random seller without attention to market prices in our model though firms also choose quality stochastically and there is both price and quality dispersion two stylized policy interventions are considered competition policy which acts to increase the number of sellers and market transparency reforms which act to increase the fraction of attentive consumers with fewer inattentive consumers firms are less likely to cheat i e cut quality which therefore improves welfare but profit and consumer surplus can either increase or decrease when there is a large number of sellers approximately half the sellers cheat regardless of the fraction of inattentive consumers and introducing more sellers boosts consumers surplus and reduces profit while the impact on welfare is ambiguous

price dispersion in duopolies with heterogeneous consumers abstract in this paper i modify varian s varian h r 1980 a model of sales american economic review 70 4 651 659 model of sales to allow for heterogeneity in consumer preferences i show that in mixed strategy equilibria each firm charges a finite number of prices using this characterization i examine the effect of consumer heterogeneity on firms optimal pricing strategies

predictable events and excess returns the case of dividend announcements abstract this paper hypothesizes that the risk per unit of time and the required rate of return are higher than normal during an event period whose timing can be predicted consistent with this hypothesis this paper presents empirical evidence indicating that the unconditional mean rate of return the variance of stock returns and their systematic risk are higher than usual during dividend announcement periods however the documented increases in the systematic risk are not large enough to fully explain the excess returns this finding is puzzling and hard to reconcile with existing theory

price promotions in emerging markets how should price promotion strategies be modified in an emerging market e g india china compared to those employed in developed markets e g usa canada specifically how should the presence of middle class consumers with limited ability to pay prevalent in an emerging market influence the depth and frequency of price promotions offered by competing firms lay intuition suggests that firms should promote more frequently and offer deeper discounts in emerging markets in order to effectively sell to limited income middle class consumers we construct a theoretical model that investigates the effect of the middle class segment on firms price promotion strategies contrary to lay intuition our analysis reveals precisely the opposite results first price promotions offered in an emerging market with middle class consumers are shallower than those offered in a developed market without middle class consumers second relatively deep price promotions occur less frequently in an emerging market compared to a developed market these theoretical findings are consistent with the empirical evidence we gathered from the supermarkets in india and in canada

truly costly sequential search and oligopolistic pricing we modify the paper of stahl 1989 stahl d o 1989 oligopolistic pricing with sequential consumer search american economic review 79 700 12 by relaxing the assumption that consumers obtain the first price quotation for free when all price quotations are costly to obtain the unique symmetric equilibrium need not involve full consumer participation the region of parameters for which non shoppers do not fully participate in the market becomes larger as the number of shoppers decreases and or the number of firms increases the comparative statics properties of this new type of equilibrium are interesting in particular expected price increases as search cost decreases and is constant in the number of shoppers and in the number of firms welfare falls as firms enter the market we show that monopoly pricing never obtains with truly costly search d 2005 elsevier b v all rights reserved

advertising brand loyalty and pricing i consider an oligopoly model where prior to price competition firms invest in persuasive advertising and induce brand loyalty in consumers who would otherwise buy the cheapest alternative on the market this setting in which persuasive advertising is introduced to homogenous product markets provides an alternative explanation for price dispersion phenomena despite ex ante symmetry the equilibrium profile of advertising outlays is asymmetric it follows that endogenously determined brand loyal consumer bases are not symmetric across firms this raises a robustness question regarding varian s model of sales where symmetry is exogenously assumed

differential information and security market equilibrium we propose a simple model of equilibrium asset pricing in which there are differences in the amounts of information available for developing inferences about the returns parame ters of alternative securities in contrast with earlier work we show that parameter uncer tainty or estimation risk can have an effect upon market equilibrium under reasonable conditions securities for which there is relatively little information are shown to have relatively higher systematic risk when that risk is properly measured ceteris paribus the initially very limited model is shown to be robust with respect to relaxation of a number of its principal assumptions we provide theoretical support for the empirical examination of at least three proxies for relative information period of listing number of security returns observations available and divergence of analyst opinion

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

search and segregation abstract consumers willingness to pay for an identical product e g as caused by differences in local income or tastes may differ greatly across locations yet while a large literature examines consumers optimal price and product search behavior under various market configurations the equilibrium effects of such consumer segregation remain unexplored to this end i study a stylized model in which two local monopolistic markets differ in size and their consumers willingness to pay after observing their native market s price a subset of flexible consumers may travel to the other market at positive cost hoping for a bargain i show that as long as the proportion of flexible high valuation consumers is not too large active and directed search to the lower valuation market will occur in equilibrium if the higher valuation market is relatively large in size complex mixed strategy pricing emerges in equilibrium for regulators increasing the fraction of flexible consumers tends to be more effective than manipulating search costs

a laboratory study of duopoly price competition with patient buyers i introduction two extreme forms of pricing behavior sometimes called the bertrand paradox and the diamond paradox emerge from a single distinguishing assumption bertrand 1883 assumes that a buyer knows ex ante the prices of all sellers and notes that with homogeneous goods a single competitive price emerges even among a small number of sellers because at any slightly higher price at least one seller can increase his profit by engaging in undercutting in diamond s 1971 model on the other hand a buyer first chooses a seller and then receives the price quote ex post even with infinitesimal search cost in equilibrium a buyer searches only one seller and all sellers charge the monopoly price the only difference between the two formulations is whether sellers price ex ante or ex post 1 intuitively however there is no strong rationale for preferring either assumption for when price information is acquired this is especially so since the law of one price is known to fail and persistent price dispersion is widely observed even in essentially homogenous goods markets e g baye morgan and scholten 2004 brynjolfsson and smith 2000 sorensen 2000 most of the theoretical literature that models price dispersion has employed costly buyer search e g salop and stiglitz 1977 1982 stahl 1989 1996 stigler 1961 or costly seller advertising butters 1977 robert and stahl 1993 to generate dispersed prices 2 gale 1988 on the other hand models price dispersion in a rather stark form using only two sellers and one buyer this can provide a modeling foundation for some types of multilateral bargaining such as in concentrated intermediate goods markets sellers are uncertain whether the buyer is receiving price offers from both ex ante pricing or one ex post pricing of them at any given time if the buyer s sample contains both offers with a positive but not certain probability gamma a unique dispersed price equilibrium exists that shifts systematically with gamma extending this static model to multiround pricing with time discounting gale examines the impact of greater buyer patience modeled as a higher discount factor on the equilibrium price level and price dispersion this is intended to approximate market conditions with many buyers where trade continues over time as can occur also in durable goods settings as buyers become more patient sellers must compete not only with the other seller but also with their own future price offers consequently the equilibrium price distribution becomes concentrated at lower prices this article presents the first laboratory experiment that studies the interaction of buyer patience and search with multiround pricing by competing sellers specifically we focus on prices posted by competing sellers in a noisy search environment where buyers can wait for more price offers this enables us to explore how the timing of buyer s purchase decisions influences sellers pricing strategy which is not captured by the stationary equilibrium of the theoretical model the experiment includes both a static treatment where agents have only one opportunity to trade each period and a dynamic treatment where trading opportunities may continue for future rounds of price offers with a positive and known probability 3 one interpretation of these single round trading and multiple round trading treatments is that the former refers to a disposable goods and the latter to a durable goods environment the model s predictions that prices decrease if the buyer is more patient or is more likely to receive both price offers are intuitive but the available evidence from previous durable goods and bargaining experiments provides only weak support for theory furthermore implications of multiple price offers from competing sellers have never been studied previously in experiments with durable goods and multiple round trading which have focused on single seller environments

deadline effects and inefficient delay in bargaining with endogenous commitment abstract bilateral sequential negotiators delay agreements until a deadline if a player that rejects an offer is subsequently committed not to accept any poorer proposal and if the common discount factor is close enough to one journal of economic literature classification numbers c7 c78 j52

a model of add on pricing this paper examines competitive price discrimination with horizontal and vertical taste differences consumers with higher valuations for quality are assumed to have stronger brand preferences two models are considered a standard competitive price discrimination model in which consumers observe all prices and an add on pricing game in which add on prices are naturally unobserved and firms may advertise a base good at a low price in hopes of selling add ons at high unadvertised prices in the standard game price discrimination is self reinforcing the model sometimes has both equilibria in which the firms practice price discrimination and equilibria in which they do not the analysis of the add on pricing game focuses on the chicago school argument that profits earned on add ons will be competed away via lower prices for advertised goods a conclusion is that add on practices can raise equilibrium profits by creating an adverse selection problem that makes price cutting unappealing although profitable when jointly adopted using add on pricing is not individually rational in a simple extension with endogenous advertising practices and costless advertising several models that could account for add on pricing are discussed

the unique equilibrium in a model of sales with costly advertising abstract we demonstrate that the varian 1980 model of sales has a unique nash equilibrium when firms incur costly advertising to compete for informed consumers the equilibrium is symmetric in particular with costly advertising the asymmetric equilibria highlighted by baye et al 1992 do not arise

aggregation and imperfect competition on the existence of equilibrium we present a new approach to the theory of imperfect competition and apply it to study price competition among differentiated products the central result provides general conditions under which there exists a pure strategy price equilibrium for any number of firms producing any set of products this includes products with multi dimen sional attributes in addition to the proof of existence we provide conditions for uniqueness our analysis covers location models the characteristics approach and probabilistic choice together in a unified framework to prove existence we employ aggregation theorems due to prekopa 1971 and borell 1975 our companion paper caplin and nalebuff 1991 introduces these theorems and develops the application to super majority voting rules we present a new approach to the theory of imperfect competition and apply it to study price competition among differentiated products the central result is that there exists a pure strategy price equilibrium for any number of firms producing any set of products in addition to the proof of existence we provide conditions for uniqueness our model both unites diverse strands of the earlier literature and opens up uncharted areas for future analysis in particular we expand the traditional one dimensional framework to allow for multi dimen sional product differentiation our approach involves twin restrictions on consumer preferences one on individuals preferences the other on the distribution of preferences across society these are generalizations of the restrictions supporting 64 majority rule presented in caplin and nalebuff 1988 to prove existence we apply a new technique of aggregation this technique is valuable in a variety of other problems in the companion paper we use the aggregation result to generalize our earlier work on 64 majority rule and to characterize the relationship between the distribution of human capital and the distribution of income caplin and nalebuff 1991 there are additional applications in statistics and in search theory we begin with a brief review of the early literature on imperfect competition describing in more detail the existence problem and previous solutions section 3 presents our twin assumptions and shows that they cover many standard cases in section 4 we introduce the aggregation theorem and use it in the analysis of demand functions the proof of existence of equilibrium is in section

strategic complementarities and search market equilibrium abstract in this paper we apply supermodular game theory to the equilibrium search literature with sequential search we identify necessary and sufficient conditions for the pricing game to exhibit strategic complementarities and prove existence of equilibrium we then show that price dispersion is inherently incompatible with strategic complementarities in the sense that the diamond paradox obtains when firms are identical and is robust within the class of search cost densities that are small near zero and support strategic complementarities we also show that a major criticism of the literature that agents act as if they know the distribution of prices can be justified in the sense of convergent best response dynamics

information gatekeepers on the internet and the competitiveness of homogeneous product markets we examine the equilibrium interaction between a market for price information controlled by a gatekeeper and the homogenous product market it serves the gatekeeper charges fees to firms that advertise prices on its internet site and to consumers who access the list of advertised prices gatekeeper profits are maximized in an equilibrium where a the product market exhibits price dispersion b access fees are sufficiently low that all consumers subscribe c advertising fees exceed socially optimal levels thus inducing partial firm participation and d advertised prices are below unadvertised prices introducing the market for information has ambiguous social welfare effects

interpreting common stock returns around proxy statement disclosures and annual shareholder meetings numerous studies have analyzed the stock market reaction to information released in proxy statements two possible biases in proxy statement research are suggested frequently misspecification of the return benchmark and a sample selection bias from analyzing only clean events this paper presents evidence that most of the conclusions of existing studies are not affected by these potential biases a significantly positive abnormal return was found around a random sample of shareholder meeting dates the result indicates that interpreting event study results for announcements occurring around annual shareholder meetings must be conducted carefully the results are consistent with the findings of kalay and loewenstein 14 who argue that risk and expected return can increase around predictable information producing events alternatively the study can be viewed as being consistent with several recent studies that find anomalous results using daily return data and large samples

simultaneous offers and the inefficiency of bargaining a two period example abstract it is shown that the pareto optimal outcomes in a two period simultaneous move bargaining model violate forwards induction rationality when the players are sufficiently patient this bargaining model describes a situation where a principal is represented by an agent whose flexibility is restricted hence a bargaining process with such agents can create costly delays the result also provides another example of the power of forwards induction and stability

bertrand equilibrium in a differentiated duopoly this paper studies the stability of price competition in a horizontally differentiated duopoly the firms demand is derived from a distribution of consumer preferences this description of the consumer sector is applicable to a large class of differentiated commodity markets including spatial competition models the author shows that there is a pure price setting equilibrium when consumer tastes are sufficiently dispersed further conditions on the dispersedness of preferences guarantee uniqueness of the equilibrium in addition the author examines the relation between consumer preferences and the competitiveness and efficiency of the equilibrium outcome copyright 1992 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association