investment and market dominance we analyze a model of oligopolistic competition with ongoing investment special cases include incremental investment patent races learning by doing and network externalities we investigate circumstances under which a firm with low costs or high quality will extend its initial lead through investments to this end we derive a new comparative statics result for general games with strategic substitutes which applies to our investment game finally we highlight plausible countervailing effects that arise when investments of leaders are less effective than those of laggards or in dynamic games when firms are sufficiently patient

models for referendum data the structure of discrete choice models for contingent valuation abstract in 1979 bishop and heberlein introduced an appealing variant of the contingent valuation method which required only yes or no responses hanemann developed a utility theoretic interpretation of the yes no responses which has helped popularize the approach recently cameron has offered another interpretation also utility theoretic which she argues is more general than the hanemann random utility model this paper compares the deterministic models suggested by hanemann and cameron showing them to be dual to each other it shows that correct specification of either function must exclude endogenous variables such as quantity demanded it also demonstrates that using utility theoretic models allows one to compare travel cost models and contigent valuation models on the basis of their implied behavior not on the unobservable surplus or variation measure

sluggish consumers an evolutionary solution to the bertrand paradox we consider an evolutionary model where sellers charge prices for a homogeneous commodity and where consumers while incompletely informed about prices decide from which seller they buy the commodity sellers revise their decisions by way of imitation and experimentation and consumers engage in search consumers are sluggish if they do not learn sellers prices with some positive probability only if consumers are not sluggish at all does economic evolution unambiguously support bertrand equilibrium if consumers are sluggish firms charge other prices as well and the evolutionary process displays a property similar to parallel pricing if consumers are extremely sluggish evolution picks up monopoly pricing journal of economic literature classification numbers c7 d43 d83 l13

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

the stability of price dispersion under seller and consumer learning in many markets it is possible to find rival sellers charging different prices for the same good earlier research has attempted to explain this phenomenon by demonstrating the existence of dispersed price equilibria when consumers must make use of costly search to discover prices we ask whether such equilibria can be learned when sellers adjust prices adaptively in response to current market conditions with consumer behavior fixed convergence to a dispersed price equilibrium is possible in some cases however once consumer learning is introduced the monopoly outcome first found by diamond journal of economic theory3 1971 156 68 is the only stable equilibrium

incentive incompatibility and starting point bias in iterative valuation questions we test for incentive incompatibility and starting point bias to describe the effects of iterative valuation questions on willingness to pay we compare double triple and multiplebounded models with data from two surveys with similar designs of the valuation questions we find that incentive incompatibility is present in both sets of data and starting point bias is present in one the efficiency of the willingness to pay estimate is improved in only one set of data the potential loss from using iterative questions without controlling for both incentive incompatibility and starting point bias is biased willingness topay estimates

market share dynamics in a duopoly model with word of mouth communication abstract we analyze dynamic price competition in a homogeneous goods duopoly where consumers exchange information via word of mouth communication a fraction of consumers who do not learn any new information remain locked in at their previous supplier in each period we analyze markov perfect equilibria in which firms use mixed pricing strategies market share dynamics are driven by the endogenous price dispersion depending on the parameters we obtain different classes of dynamics when firms are impatient there is a tendency towards equal market shares when firms are patient there are extended intervals of market dominance interrupted by sudden changes in the leadership position

interval estimates of non market resource values from referendum contingent valuation surveys contingent valuation methods cvm have attracted considerable attention in recent years as researchers have begun to resort to survey methods to elicit individual values for non market goods such as environmental resources or public goods cummings brookshire and schulze 1986 and mitchell and carson 1989 offer comprehensive assessments of these methods cvm survey questions come in a variety of forms one format which has proven to be popular is called the discrete choice or take it or leave it referendum or closedended question originally implemented in the literature by bishop and heberlein 1979 since respondents find it very difficult to identify precisely their true point value of access to some resource or public good open ended valuation questions can be unreliable or can discourage response in contrast most people are familiar with being confronted by a posted price for a good and with deciding whether or not they would buy at that price this is the strategy behind discrete choice cvm questions a different hypothetical price is offered to each respondent and by their yes no response to the question of whether they would be willing to pay this price the researcher gains information about their true underlying point value one persistent difficulty with the econometric techniques that are currently used most widely to analyze referendum contingent valuation data is the absence of confidence intervals for the ultimate value estimates early empirical applications approximate mean valuations using a truncated mean based on a logit model with the upper limit being the highest bid value in the sample unfortunately the variance of this estimated mean cannot easily be recovered from the numerical integration procedure commonly used to calculate the

a model of the evolution of duopoly does the asymmetry between firms tend to increase or decrease this paper is an attempt to identify some of the factors that affect the evolution of market structure in a model of dynamic competition between two firms the stochastic evolution of the state of competition depends on the respective effort rates of the firms the question is whether the current leader works harder than the laggard does the gap between firms tend to increase or decrease we show that several effects are at work the state tends to evolve in the direction where joint payoffs are greater since joint payoffs are related to joint product market profits less joint effort costs there are two classes of effect the joint profit effect and various joint cost effects the latter result in part from the pattern of profits and in part from endpoint effects that give relief from efforts asymptotic expansions illuminate these influences moreover we show by numerical simulation that there is another kind of joint cost effect the pattern of joint effort costs can influence the pattern of evolution of market structure and the evolution of the pattern of market structure can influence the pattern of efforts in a mutually self reinforcing manner in particular there may be equilibria in which this last effect means that the laggard works harder than the leader even though all the other effects work in favour of the leader

the learning curve market dominance and predatory pricing sufficient conditions for id and iid are given in the case of two step learning in which a firm reaches the bottom of its learning curve after just two sales however examples are also constructed for the two step learning case in which neither id nor iid holds it is also shown that in equilibrium iid implies that learning is privately disadvantageous although it is socially advantageous finally introducing avoidable fixed costs and possible exit into the model yields a new theory of predatory pricing based on the learning curve hypothesis

consumer search with observational learning this article studies observational learning in a consumer search environment consumers observe the purchasing decision of a predecessor with similar preferences consumers rationally emulate by initiating their search at the firm from which their predecessor purchased free riding on search effort and reacting less to price changes prices are nonmonotone in search costs and may be as low as marginal costs we discuss several extensions and show that the effect of emulation on prices is stronger when i the number of firms increases ii consumers first visits are more elastic with respect to market shares and iii prices are adjusted more frequently

confidence intervals for evaluating benefits estimates from dichotomous choice contingent valuation studies i evaluate the potential usefulness of nonmarket valuation concepts and techniques from environmental economics for improving wildlife conservation the concepts include distinguishing between on site recreation use value and off site passive use or

the existence of equilibrium in discontinuous economic games ii applications in part i of this study we established two existence theorems for mixed strategy equilibrium in games with discontinuous payoff functions see theorems 4 4 and 5 5 in dasgupta and maskin 1986 hereafter d m 1986 in this second part we use the second of these two theorems to prove the existence of mixed strategy equilibrium in some wellknown discontinuous economic games that fail to have pure strategy equilibria the models we analyse are the bertrand edgeworth example of price setting duopolists with capacity constraints see section 2 2 price competition among firms producing differentiated products hotelling 1929 and d aspremont gabszewicz and thisse 1979 see section 2 3 spatial competition eaton and lipsey 1975 and shaked 1975 see section 3 and models of market dependent information rothschild and stiglitz 1976 and wilson 1977 section 4 the paper concludes section 5 with a classification of these models

a new paradigm for valuing non market goods using referendum data maximum likelihood estimation by censored logistic regression abstract this paper challenges the w m hanemann amer j agr econom 66 332 341 1984 and c sellar j p chavas and j r stoll j environ econom management 13 382 390 1986 utilizations of logit models to estimate the value of non market resources from referendum survey data these data are more informative than conventional choice data the random utility interpretation of logit models is therefore too restrictive bypassing the utility function entirely it will be shown that parameters and standard errors for utility theoretic inverse hicksian demand functions can be extracted directly and much more simply estimated demand functions need not be limited to those corresponding to the linear in parameters utility difference specifications which can be handled by packaged logit programs

validation of empirical measures of welfare change a comparison of nonmarket techniques since the passing of the flood control act of 1936 the attention of many resource economists has been directed towards measuring the benefits and costs of alternative uses of natural resources increasingly it has been recognized that the value of some of these uses is not explicitly determined through market transactions this has led to the focus of much attention upon the development of nonmarket methods to estimate the value of these uses in the 1940s the groundwork for the travel cost method was established by hotelling prewitt 1949 following this in the 1960s davis initiated the basic foundation for bidding methods davis 1963 which were later to be subsumed under the heading of contingent valuation methods brookshire randall and stoll 1980 schulze d arge and brookshire 1981 thayer 1981 both of these methods will be further discussed below in addition to these two methods a third approach the unit day value method has been recognized as acceptable but not preferred for the valuation of recreational uses of water and related land resources dwyer kelley and bowes 1977 u s water resources council 1979 given the existence of alternative methods of estimating the value of resource uses several obvious questions arise one of the first of these is under what circumstances is each method most appropriate existing literature has focussed sufficiently on this question and pointed out limitations of each especially the travel cost method and unit day value methods brookshire ives and schulze 1976 dwyer kelly and bowes 1977 freeman 1979 mcconnell 1975 randall ives and eastman 1977 schulze d arge and brook

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

a foundation for markov equilibria in sequential games with finite social memory we study stochastic games with an infinite horizon and sequential moves played by an arbitrary number of players we assume that social memory is finite every player except possibly one is finitely lived and cannot observe events that are sufficiently far back in the past this class of games includes games between a long run player and a sequence of short run players and games with overlapping generations of players an equilibrium is purifiable if some close by behaviour is consistent with equilibrium when agents payoffs in each period are perturbed additively and independently we show that only markov equilibria are purifiable when social memory is finite thus if a game has at most one long run player all purifiable equilibria are markov

word of mouth communication and social learning this paper studies the way that word of mouth communication aggregates the information of individual agents we find that the structure of the communication process determines whether all agents end up making identical choices with less communication making this conformity more likely despite the players naive decision rules and the stochastic decision environment word of mouth communication may lead all players to adopt the action that is on average superior these socially efficient outcomes tend to occur when each agent samples only a few others i introduction economic agents must often make decisions without knowing the costs and benefits of the possible choices given the frequency with which such situations arise it is understandable that agents often choose not to perform studies or experiments but instead rely on whatever information they have obtained via casual word of mouth communication reliance on this sort of easily obtained information appears to be common in circumstances ranging from consumers choosing restaurants or auto mechanics to business managers evaluating alternative organizational structures this paper studies two related environments in arguing that individuals reliance on word of mouth communication has interesting implications for their aggregate behavior first motivated by the diffusion of new technologies we consider a choice between two competing products with unequal qualities or payoffs and show that the structure of communication is important in determining whether the population as a whole is likely to learn to use the superior product second we consider a choice between two products or practices that are equally good and ask whether consumers are likely to herd onto a single choice or whether diversity will obtain even in the long run we explore the implications of word of mouth communication in a simple nonstrategic environment there is a large population of identical players each of whom repeatedly chooses between two possible actions each player s payoff is determined by his own

existence and persistence of price dispersion an empirical analysis the hebrew university of jerusalem and nber using a unique data set on store level monthly prices of four homogenous products sold in israel i study the existence and characteristics of the dispersion of prices across stores as well as its persistence over time i find that price dispersion prevails even after controlling for observed and unobserved product heterogeneity moreover intra distribution mobility is significant stores move up and down the cross sectional price distribution thus consumers cannot learn about stores that consistently post low prices as a consequence price dispersion does not disappear and persists over time as predicted by varian s 1980 model of sales

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

a theory of dynamic oligopoly ii price competition kinked demand curves and edgeworth cycles we provide game theoretic foundations for the classic kinked demand curve equilibrium and edgeworth cycle we analyze a model in which firms take turns choosing prices the model is intended to capture the idea of reactions based on short run commitment in a markov perfect equilibrium mpe a firm s move in any period depends only on the other firm s current price there are multiple mpe s consisting of both kinked demand curve equilibria and edgeworth cycles in any mpe profit is bounded away from the bertrand equilibrium level we show that a kinked demand curve at the monopoly price is the unique symmetric renegotiation proof equilibrium when there is little discounting we then endogenize the timing by allowing firms to move at any time subject to short run commitments we find that firms end up alternating thus vindicating the ad hoc timing assumption of our simpler model we also discuss how the model can be enriched to provide explanations for excess capacity and market sharing keiiwords tacit collusion markov perfect equilibrium kinked demand curve edgeworth cycle excess capacity market sharing endogenous timing

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

actual averting expenditure versus stated willingness to pay the purpose of this study is to perform a complete comparison of actual averting expenditure and stated willingness to pay measures and to determine if the averting expenditure is a lower bound of the willingness to pay measured from contingent valuation experiment as suggested by literature in addition to the single value comparison bootstrap krinsky and robb jackknife and cameron are four simulation methods used to calculate confidence intervals for response function sample sizes of 100 200 and 1000 are simulated 100 and 200 times respectively a set of data with 540 households from a contingent policy referendum survey is employed for our purpose under a specific level of bod improvement a one to one single mean value comparison of the actual averting expenditure is greater than the mean willingness to pay from utility difference model the empirical results are consistent with the theoretical expectation for expenditure difference that averting expenditure is a lower bound of willingness to

why market shares matter an information based theory consider a duopoly market in which consumers have heterogeneous information about the quality differential q of the two goods when firms are ignorant about q consumers rationally believe that a firm with high market shares is likely to produce a high quality good as a result firms try to signal jam the inferences of consumers and compete for market shares beyond the level explained by short run profit maximization when firms know q multiple equilibria may exist but there is always one equilibrium in which market shares signal quality and then the market tends to be more competitive

welfare measurements using contingent valuation a comparison of techniques three commonly used techniques of asking contingent valuation questions are compared iterative bidding payment cards and dichotomous choice the results reveal that no single contingent valuation technique is neutral in the elicitation of hicksian surplus and each technique has its strengths and weaknesses the iterative bidding estimates contain a starting point bias while the payment card and dichotomous choice estimates were influenced by the interviewers soliciting the contingent values finally the analysis of dichotomous choice responses involves unresolved issues that warrant further investigation on the other hand dichotomous choice is the easiest technique to administer in a survey setting

the existence of equilibrium in discontinuous economic games i theory the article presents information about the existence of equilibrium in discontinuous economic games in this paper and its sequel presents study the existence of nash equilibrium in games where agents payoff functions are discontinuous the enquiry is motivated by a number of recent studies that have uncovered serious existence problems in seemingly innocuous economic games in the sequel to this paper authors have explained the utility function in the economic games referred to earlier are neither continuous nor quasi concave however they demonstrate that the payoff functions in mildly modified versions of these constructs exhibit two weaker forms of continuity which together with the requirement of quasi concavity suffice for the existence of an equilibrium from this one may conclude that at least in the modified versions of these models discontinuities in the payoff functions are not the real source of the problem rather it is the failure of the payoff functions to the quasi concave which is responsible for the non existence of equilibrium these observations bear on the existence of nash equilibrium in pure strategies

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

dynamic price competition with network effects i consider a dynamic model of competition between two proprietary networks consumers die and are replaced with a constant hazard rate and firms compete for new consumers to join their network by offering network entry prices i derive a series of results pertaining to a existence and uniqueness of symmetric equilibria b monotonicity of the pricing function e g larger networks set higher prices c network size dynamics increasing dominance vs reversion to the mean and d firm value how it varies with network effects finally i apply my general framework to the study of termination charges in wireless telecommunications i consider various forms of regulation and examine their impact on firm profits and market share dynamics

market share dynamics and the persistence of leadership debate this paper introduces a novel analysis of the classic persistence of leadership question and applies it to a newly constructed dataset for japanese manufacturing the analysis rests on an appeal to an empirical scaling relationship between current market share and the variance of changes in market share this relationship provides a powerful model selection criterion for candidate models of market share dynamics it also makes it feasible even in small datasets to test directly for the properties of the first passage times corresponding to loss of leadership

social capital and loan repayment performance in northern vietnam this study analyses the effects of social capital on the loan repayment behavior of borrowers in vietnam in the context of agricultural economics an innovative data collection approach is used that originates from the field of sociology a personal network survey is carried out to measure the individual social capital of borrowers social capital variables are defined according to tie strength bonding bridging and social distance linking between the respondent and his her network member social capital has a significant and positive influence on the rescheduling of loans however we find no significant evidence for an effect of social capital on late payment of principal or interest

information acquisition and reputation dynamics we study dynamic incentives and behaviour in markets with costly discovery of past transactions in our model a sequence of short lived customers interact over time with a single long lived firm that privately knows its type good or opportunistic customers must pay to observe the firm s past behaviour we characterize the equilibrium structure that features accumulation consumption and restoration of reputation the opportunistic firm deliberately builds its reputation up to a point where the maximum periods of information acquired by customers do not reveal past opportunistic behaviour and exploits the customers who most trust the firm copyright 2011 oxford university press

the dynamic instability of dispersed price equilibria abstract we adopt an evolutionary framework to explain price dispersion as a time varying phenomenon by developing a finite strategy analogue of the burdett and judd 1983 price dispersion model we show that all dispersed price equilibria are unstable under the class of perturbed best response dynamics instead numerical simulations using the logit dynamic show that price dispersion manifests itself as a limit cycle we verify that limit cycles persist even when the finite strategy model approaches the original continuous strategy model for a particularly simple case of the model we prove the existence of a limit cycle

is bigger better customer base expansion through word of mouth reputation a model of gradual reputation formation through a process of continuous investment in product quality is developed we assume that the ability to produce high quality products requires continuous investment and that as a consequence of informational frictions such as search costs information about firms past performance diffuses only gradually in the market this leads to a dual process of growth of a firm s customer base and an increase in the firm s investment in quality the model predicts therefore that the longer its tenure as a high quality producer the more a firm invests in quality we relate this finding to empirical work on online commerce as well as on traditional industries

on the informational role of quantities durable goods and consumers word of mouth communication a dynamic incomplete information game is set up to study the introduction of a durable good when consumers can learn its quality from previous buyers high sales today imply fewer potential buyers tomorrow but each buyer will have better information about the good consumers are fully rational and can update their beliefs even when they do not directly receive information in equilibrium no news is bad news a low quality firm follows a fly by night strategy randomizing over the timing of sales a high quality firm spreads out its sales more smoothly solving a stochastic dynamic programming problem copyright 1997 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

a contingent valuation estimate of the benefits of wolves in minnesota in this paper we estimate the willingness topay for a wolf management plan and a wolfdamage plan in minnesota using the contingentvaluation method the theoretical definition ofwillingness to pay for wolf protection iscomposed of use and non use values weincorporate a don t know response option in thedichotomous choice valuation questions a largenumber of respondents answered don t know themultinomial logit model is used todifferentiate between don t know and noresponses non use motives are importantfactors that explain willingness to pay we usethese benefit estimates in combination with twoalternative cost estimates to consider theefficiency of the wolf management and damageplans both plans have estimated benefitsgreater than costs