analyst reputation communication and information acquisition earlier studies have shown that reputational concerns tend to reduce agents opportunistic behavior however a recent study by morris argued that analysts experts reputational concerns may discourage truthful communication when they try to avoid being perceived as being misaligned with investors in this paper i examine the effect of reputational concerns on communication in a setting where analysts can choose their precision endogenously because both misaligned and aligned analysts want investors to trust their reports in the future both will aim to build a reputation for being aligned in equilibrium aligned analysts will acquire more information than misaligned analysts as a result investors may favorably update their beliefs about the analysts type when the report is proven to be accurate therefore both types of analysts will have reputational incentives to communicate truthfully the paper also derives conditions under which the analysts reputational concerns have a nonmonotonic impact on aligned analysts equilibrium precision choices and investors welfare

product quality consumption externalities and the role of national treatment abstract article iii of the wto national treatment limits domestic policy in an effort to curtail protectionist discrimination against foreign products in this paper we examine the role of national treatment and prominent article xx exceptions when goods are vertically differentiated and generate consumption externalities we study the domestic policy choices of two countries first stage problem and quantity and price equilibria in two product markets second stage problem under a strict application of article iii and compare them to the policy choices and product market equilibria prevailing when countries can misrepresent external damages and discriminate while one may expect that high externalities would lead to a greater need for exceptions to equal treatment we show that this is often not the case and furthermore that non discrimination can lead to a cleaner world environment

pollution havens endogenous environmental policy and foreign direct investment in an increasingly integrated world economy countries may have greater incentives to weaken environmental policy as disguised protection intended to give a competitive edge to local firms this may generate pollution havens as firms relocate in response to different environmental policies foreign direct investment fdi weakens profit shifting policy considerations while increasing environmental damages but at the same time may provide external benefits we derive conditions under which the fdi recipient country has an incentive to manipulate its environmental standard to prevent or attract fdi potentially eliminating or creating pollution havens in addition to examining the impact of fdi on the equilibrium state of the environment

reputation and imperfect information abstract a common observation in the informal literature of economics and elsewhere is that is multistage games players may seek early in the game to acquire a reputation for being tough or benevolent or something else but this phenomenon is not observed in some formal game theoretic analyses of finite games such as selten s finitely repeated chain store game or in the finitely repeated prisoners dilemma we reexamine selten s model adding to it a small amount of imperfect or incomplete information about players payoffs and we find that this addition is sufficient to give rise to the reputation effect that one intuitively expects

a theory of credibility this paper presents models in which one agent must decide whether to trust another whose motives are uncertain reliability can only be communicated through actions in this context it pays for people to build a reputation based on reliable behaviour someone becomes credible by consistently providing accurate and valuable information or by performing useful services the theory provides a justification for long term arrangements without binding contracts it also describes those situations where it pays an agent to cash in on his reputation many decisions depend on trusting someone consumers must decide whether to believe advertisements banks need to judge the reliability of loan applicants and employers must decide how much responsibility to delegate to their employees this paper attempts to model situations that arise when someone is uncertain about whether to trust the people he deals with in this context reputations for reliability are valuable an agent becomes credible by consistently providing accurate valuable information or by always acting responsibly i analyse a series of simple abstract models of information transmission in the basic model there are two agents the sender s and the receiver r who are to play the game a known finite number of times at each stage both players learn the value of a parameter measuring the importance of that period s play of the game that is the value of making a correct decision and s obtains payoff relevant information s then sends a signal to r who makes a decision that affects the welfare of both players after both players learn the consequences of r s decision the process repeats at each stage r must decide what action to take in order to do that he must assess the credibility of s the difficulty arises because r is uncertain about s s preferences when play begins i model this by assuming that with positive probability s has identical preferences to r s is a friend and with positive probability s has completely opposed preferences to r s is an enemy this uncertainty creates a trade off for enemy senders at each stage providing honest information enhances s s reputation but only at the expense of foregoing an opportunity for immediate gain by duping r the possibility that s is a friend lends credibility to what he says but this credibility may also be exploited by an enemy s the principal equilibrium has the following form in the basic model where s has no control over the importance of a given play s typically conveys accurate information for the first several periods r raises the probability he places on s being friendly after receiving accurate information if he believes that an enemy would have lied to him with positive probability the more important the information the more likely an enemy will attempt to deceive r an enemy will eventually take advantage of r by misleading him when this happens the sender loses all opportunities for deception in the future i

a theory of ambiguity credibility and inflation under discretion and asymmetric information this paper develops a positive theory of credibility ambiguity and inflation under discretion and asymmetric information the monetary policymaker maximizes his own politically motivated objective function that is positively related to economic stimulation through monetary surprises and negatively related to monetary growth the relative importance he assigns to each target shifts stochastically through time his current preference trade off is known to him but not to the public when choosing the state contingent path of money growth for the present and the future the policymaker compares the benefits from current stimulation with the costs associated with higher future inflation expectations current monetary growth conveys information to the public about future money growth because there is persistence in the policymaker s objectives although expectations are rational information is imperfect because monetary control procedures are imprecise as a result the public cannot correctly distinguish persistent changes of emphasis on different policy objectives from transitory monetary control errors the public becomes aware of changes gradually by observing past monetary growth credibility is defined in terms of the speed with which the public recognizes changes in the objectives of the policymaker credibility is lower the noisier monetary control and the more stable the objectives of the policymaker looser monetary control and a higher degree of time preference on the part of the policymaker induce him to produce higher and more variable monetary growth when the policymaker is free to determine the accuracy of monetary control he does not always choose the most effective control available in spite of the fact that monetary surprises always have an expected value of zero the reason is that ambiguous control procedures enable the policymaker to generate positive surprises when he cares more than on average about economic stimulation he leaves the inevitable negative surprises for periods in which he cares more about inflation prevention this result provides an explanation for the fed s preference for ambiguity recently documented by goodfriend 1986 the policymaker is more likely to pick more ambiguous control procedures the more uncertain his objectives and the higher his time preference the paper also provides a theoretical underpinning for the well documented crosscountry positive correlation between the level and the variability of inflation

the burden of proof in trade disputes and the environment the wto leaves discretion over environmental policies to its members but requests that a fundamental non discrimination principle is respected national treatment nt the provision seeks to prevent protectionist use of domestic policy instruments requesting that when an imported product is sufficiently similar to a domestic product they are treated identically wto adjudicators will often face severe informational problems in environmental disputes important for the practical implementation of nt is therefore the allocation of the burden of proof bop this paper highlights basic implications of the bop for the occurrence of judicial errors for the environment and for welfare using a setting where nt serves its intended role of supporting negotiated tariff liberalization the paper suggests that nt may indeed constrain environmental policies but that this may be desirable from an efficiency point of view also bop rules that benefit the environment may not benefit global welfare and conversely

persuasive communication when the sender s incentives are uncertain abstract we study persuasion in a modified crawford sobel sender receiver game in which the receiver makes a binary decision to accept or reject a good recommended by the sender the good s quality and the sender s type neutral or biased are not observable to the receiver these alterations yield a simple model and a unique truth telling equilibrium in which neutral senders who observe different qualities fully separate but can only communicate low quality levels accurately biased senders adopt a mixed strategy that can successfully persuade the receiver to accept the good most of the time when the sender s degree of bias is continuously distributed a truth telling equilibrium does not exist nonetheless a partition equilibrium exists for any given number of partitions on the message space

do countries falsify economic data strategically some evidence that they might we find evidence supporting the hypothesis that countries at times misreport their economic data in a strategic manner among those suspected are countries with fixed exchange rate regimes high negative net foreign asset positions or negative current account balances which corroborates the intuition developed with a simple economic model we also find that countries with bad institutional quality rankings and those in africa middle east eastern europe and latin america release economic data of questionable veracity our evidence calls for models with public signals to consider strategic misinformation and for establishing independent statistical agencies to assure the delivery of high quality economic data

forward guidance communication commitment or both abstract forward guidance has been suggested as a form of commitment odyssean by the policymaker or as a way of conveying information delphic i analyze the interaction between households and the central bank as a game in which the central bank sends messages without private information the set of equilibrium payoffs is independent of any announcements pure odyssean forward guidance is redundant with private information communication can have social value forward guidance is well suited to leverage preexisting credibility to communicate a central bank s private information about its own preferences or beliefs

on the role of retaliation in trade agreements this paper analyzes the role of retaliation in trade agreements it shows that in the presence of private information retaliation can always be used to increase the welfare derived from such agreements by the participating governments in particular it is shown that retaliation is a necessary feature of any efficient equilibrium we argue that retaliation would not be necessary if governments could resort to international transfers or export subsidies to compensate for terms of trade externalities within the current world trading system though in which transfers are seldom observed whereas export subsidies are prohibited the use of the remaining trade instruments in a retaliatory fashion might be optimal the model is used to interpret the retaliatory use of antidumping observed in the last decades and the proliferation of these measures relative to other trade remedies

repeated games with long run and short run players this paper studies the set of equilibrium payoffs in repeated games with long and short run players and little discounting because the short run players are unconcerned about the future each equilibrium outcome is constrained to lie on their static reaction best response curves the natural extension of the folk theorem to games of this sort would simply include this constraint in the definitions of the feasible payoffs and minmax values in fact this extension does obtain under the assumption that each player s choice of a mixed strategy for the stage game is publicly observable but in contrast to standard repeated games the set of equilibrium payoffs is different if players can observe only their opponents realized actions

careerist experts and political incorrectness abstract while political correctness is a dominant norm in many public situations we also observe behaviors that are apparently politically incorrect often from professionals and experts this paper examines the flip side of political correctness as analyzed in morris 2001 to shed some light on the elusive notion of political incorrectness and elucidate its equilibrium and welfare properties we show that there are circumstances in which unbiased experts deliberately take a politically incorrect stance out of reputational concerns and identify key elements which give rise to this perverse reputational incentive the results suggest that political incorrectness cannot necessarily be viewed as a sign of blunt honesty when informed experts have long term reputational concerns we also examine the welfare consequences of political incorrectness and argue that this form of information manipulation can be beneficial under some conditions

does insider trading raise market volatility this paper studies the role of insider trading in explaining cross country differences in stock market volatility it introduces a new measure of insider trading the central finding is that countries with more prevalent insider trading have more volatile stock markets even after one controls for liquidity maturity of the market and the volatility of the underlying fundamentals volatility of real output and of monetary and fiscal policies moreover the effect of insider trading is quantitatively significant when compared with the effect of economic fundamentals

a monopolistic market for information abstract we analyze a model where traders buy information from a monopolistic seller which is subsequently used in a speculative market in order to overcome the dilution in the value of information due to its leakage through informative prices the seller of information may prefer to sell noisier versions of the information he actually has moreover to obtain higher profits it is desirable for the seller to sell different signals to different traders so that the added noise realizations do not affect equilibrium prices one way of doing so which does not require discrimination is to sell identically distributed personalized signals to each of a large number of traders

trends and cycles in macroeconomic time series two structural time series models for annual observations are constructed in terms of trend cycle and irregular components the models are then estimated via the kalman filter using data on five u s macroeconomic time series the results provide some interesting insights into the dynamic structure of the series particularly with respect to cyclical behavior at the same time they illustrate the development of a model selection strategy for structural time series models

national treatment in the gatt the national treatment nt clause is the first line defense in the gatt and in most other trade agreements against opportunistic exploitation of the inevitable incompleteness of the agreement this paper examines the role of nt as it applies to internal taxation under the gatt it is shown that despite severely restricting the freedom to set internal taxes nt may improve government welfare but it will not completely solve the incomplete contract problem it is meant to remedy furthermore it requires a high degree of economic sophistication on behalf of trade negotiators in order for this beneficial effect to materialize

timing decisions in organizations communication and authority in a dynamic environment this paper develops a theory of how organizations make timing decisions we consider a problem where an uninformed principal decides when to exercise an option and interacts with an informed but biased agent this problem is common examples include headquarters deciding when to close a plant drill an oil well or launch a product because time is irreversible the direction of the agent s bias is crucial for communication and allocation of authority when the agent favors late exercise centralized decision making where the principal retains authority and communicates with the agent often features full information revelation but ine cient delay delegation is never optimal in this case in contrast when the agent favors early exercise communication under centralized decision making is partial while option exercise is unbiased or delayed delegation is optimal if the bias is small or delegation can be timed thus delegating decisions such as plant closures is never optimal while delegating decisions such as product launches may be optimal

competence implies credibility the credibility of monetary policy under discretion has been traditionally linked to the central bank s conservatism we show that another trait of the central bank cb her competence at doing her job or reputation thereof can be just as important to make her policy credible and transparent we analyze a static barro and gordon 1983 s game where the effects of monetary policy depend on an unknown state of the economy the cb forms her own private and imprecise view of this state that she may announce to p in a cheap talk game to explain and motivate her policy intentions the precision of the noise in the cb s view measures her competence the more accurate her assessment the clearer an idea she has about what to do the fineness of the equilibrium message space measures monetary policy s transparency in any equilibrium of the cheap talk game the cb credibly announces one of finite inflation targets that differ by at least a multiple of the inflation bias competence ratio if this ratio is too large the cb can credibly communicate only the direction of monetary policy as the cb s competence rises and this ratio falls p knows that the cb puts increasing weight on pursuing her objective targets relative to surprising expectations to stimulate output therefore the equilibrium message space becomes finer a more competent cb is also less likely to erroneously observe extreme realizations of the shocks so she is more able tofine tune expectations at times of business as usual

trade skirmishes and safeguards a theory of the wto dispute settlement process i propose a framework within which to interpret and evaluate the major reforms introduced to the gatt system in its transition to the wto in particular i examine the wto agreement on safeguards that has replaced the gatt escape clause article xix and the dispute settlement process dsp that resembles a court of law under the wto using this framework i interpret the weakening of the reciprocity principle under the agreement on safeguards as an attempt to reduce e ciency reducing trade skirmishes the dsp is interpreted as an impartial arbitrator that announces its opinion about the state of the world when a dispute arises among member countries i demonstrate that the reforms in the gatt escape clause should be bundled with the

gambling reputation repeated bargaining with outside options we study the role of incomplete information and outside options in determining bargaining postures and surplus division in repeated bargaining between a long run player and a sequence of short run players the outside option is not only a disagreement point but reveals information privately held by the long run player in equilibrium the uninformed short run players offers do not always respond to changes in reputation and the informed long run player s payoffs are discontinuous the long run player invokes inefficient random outside options repeatedly to build reputation to a level where the subsequent short run players succumb to his extraction of a larger payoff but he also runs the risk of losing reputation and relinquishing bargaining power we investigate equilibrium properties when the discount factor goes to 1 and when the informativeness of outside options diffuses in both cases bargaining outcomes become more inefficient and the limit reputation building probabilities are interior publication abstract

predation reputation and entry deterrence abstract economists often argue that predatory practices are irrational since there exist cheaper or more certain means to gain or maintain a monopoly our gametheoretic equilibrium analysis suggests that if a firm is threatened by several potential entrants then predation may be rational against early entrants even if it is costly when viewed in isolation because it yields a reputation which deters other entrants asymmetric information plays a crucial role in our analysis since it provides the rationale for entrants to base their expectations of the firm s future behavior on its past actions the analysis also suggests methods to treat general reputational phenomena

national treatment at the wto the roles of product and country heterogeneity this paper analyzes the world trade organization s wto s national treatment nt clause in a two country model where quality of goods and or market size are heterogenous across countries when market size is symmetric across countries a reciprocal nt agreement i benefits the high quality country ii hurts the low quality country and iii delivers higher aggregate world welfare however such an agreement can arise in equilibrium if the high quality country s market is relatively bigger and the quality gap between goods is small i e goods are sufficiently alike the qualitative nature of these results does not change when quality is endogenously determined

an introduction to applicable game theory this paper offers an introduction to game theory for applied economists i try to give simple definitions and intuitive examples of the basic kinds of games and their solution concepts there are four kinds of games static or dynamic and complete or incomplete information complete information means there is no private information the corresponding solution concepts are nash equilibrium in static games of complete information backwards induction or subgame perfect nash equilibrium in dynamic games of complete information bayesian nash equilibrium in static games with incomplete information and perfect bayesian or sequential equilibrium in dynamic games with incomplete information the main theme of the paper is that these solution concepts are closely linked as we consider progressively richer games we progressively strengthen the solution concept to rule out implausible equilibria in the richer games that would survive if we applied solution concepts available for simpler games in each case the stronger solution concept differs from the weaker concept only for the richer games not for the simpler games

quality disclosure and certification theory and practice this essay reviews the theoretical and empirical literature on quality disclosure and certification after comparing quality disclosure with other quality assurance mechanisms and describing a brief history of quality disclosure we address two sets of theoretical issues first why don t sellers voluntarily disclose through a process of unraveling and given the lack of unraveling is it desirable to mandate seller disclosure second when we rely on certifiers to act as the intermediary of quality disclosure do certifiers necessarily report unbiased and accurate information we further review empirical evidence on these issues with a particular focus on healthcare education and finance the empirical review covers quality measurement the effect of third party disclosure on consumer choice and seller behavior as well as the economics of certifiers jel d18 k32 l15 m31

traders vs relationship managers reputational conflicts in full service investment banks we present a model that explains why investment bankers struggle to manage conflicts of interest banks can build a type reputation for technical competence by performing complex deals that may not serve their clients interest on the other hand banks can sustain a behavioral reputation by refraining from doing so a behavioral reputation is a luxury reserved for banks that have proven their abilities the model sheds light on conflicts between the trading and advisory divisions of investment banks as well as the consequences of technological change for time variation in the relative strength of behavioral and type reputation concerns

stock price manipulation it is generally agreed that speculators can make profits from insider trading or from the release of false information both forms of stock price manipulation have now been made illegal in this article the authors ask whether it is possible to make profits from a different kind of manipulation in which an uninformed speculator simply buys and sells shares they show that in a rational expectations framework where all agents maximize expected utility it is possible for an uninformed manipulator to make a profit provided investors attach a positive probability to the manipulator being an informed trader article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

insider trading in a rational expectations economy it is often argued that efficiency considerations require society to freely permit insider trading in this article an opposing efficiency argument is formalized the model incorporates an investment stage followed by a trading stage if outsiders expect insiders to take advantage of them in trading outsiders will reduce their investment the insiders loss from this diminished investor confidence may more than offset their trading gains consequently a prohibition on insider trading may effect a pareto improvement insiders are made better off if they can precommit not to trade on their privileged information govemment regulation accomplishes exactly this jel 022 026 313 the traditional rationale articulated for insider trading regulation and other securities law is that such rules promote confidence in markets indeed president franklin d roosevelt justified the first major u s securities legislation by saying it should give impetus to honest dealing in securities and thereby bring back public confidence similar language is still invoked half a century later in connection with enforcement efforts against insider trading and in proposals for tightened stock

national treatment and the optimal regulation of environmental externalities we analyze the role of national treatment in the regulation of environmental product standards for an open economy a social planner uses product standards to control emissions from the consumption of a traded good we show that whether national treatment of standards interferes with welfare maximizing policy depends on the instruments available to the policy maker consumption or emissions tax and differences in the cost of complying with the standard we also highlight the asymmetric incidence of the domestic and import product standard when taxes are suboptimal this asymmetric incidence can also cause welfare maximizing policy to violate national treatment on analyse le role du principe de traitement identique des entites domestiques ou importees dans la reglementation des normes environnementales dans une economie ouverte un gouvernement utilise des normes pour controler les emissions decoulant de la consommation d un produit transige internationalement on montre que le fait que le traitement identique des normes va ou non interferer avec l objectif poursuivi qui est de maximiser le niveau de bien etre va dependre de l ensemble des instruments disponibles pour l architecte des politiques une taxe sur la consommation ou sur les emissions et des differences dans les couts a encourir pour se conformer aux normes on souligne aussi l incidence asymetrique des normes sur les produits domestiques et importes quand les taxes sont sous optimales cette incidence asymetrique peut faire que la politique qui vise la maximisation du bien etre soit en violation du principe de traitement identique

bubbles and persuasion with uncertainty over market sentiment abstract recent empirical studies suggest that during times of unexpected innovation agents heterogeneously update their beliefs about an asset fundamental value and are uncertain of other agents beliefs about it in this paper i show that when there is uncertainty over the market sentiment defined as other investors beliefs about an asset fundamental value market manipulation can act through a previously unconsidered channel by misleading agents learning on the market sentiment this novel type of market manipulation could strengthen existing financial bubbles or even give rise to new ones

media capture in a democracy the role of wealth concentration abstract since objective news coverage is vital to democracy captured media can seriously distort collective decisions the current paper develops a voting model where citizens are uncertain about the welfare effects induced by alternative policy options and derive information about those effects from the mass media the media might however secretly collude with interest groups in order to influence the public opinion in the case of voting over the level of a productivity enhancing public bad it is shown that an increase in the concentration of firm ownership makes the occurrence of media bias more likely although media bias is not always welfare worsening conditions for it to raise welfare are restrictive

ratings shopping and asset complexity a theory of ratings inflation abstract many identify inflated credit ratings as one contributor to the recent financial market turmoil we develop an equilibrium model of the market for ratings and use it to examine possible origins of and cures for ratings inflation in the model asset issuers can shop for ratings observe multiple ratings and disclose only the most favorable before auctioning their assets when assets are simple agencies ratings are similar and the incentive to ratings shop is low when assets are sufficiently complex ratings differ enough that an incentive to shop emerges thus an increase in the complexity of recently issued securities could create a systematic bias in disclosed ratings despite the fact that each ratings agency produces an unbiased estimate of the asset s true quality increasing competition among agencies would only worsen this problem switching to an investor initiated ratings system alleviates the bias but could collapse the market for information

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

trading rules and the environment does equal treatment lead to a cleaner world abstract in this paper we consider a three stage game in the context of a competing exporters model to compare and contrast the effects of discriminatory and uniform most favored nation mfn tariffs on countries choice over environmental standards for varying degrees of pollution spillovers because of the presence of punishment effects and stronger own and cross tariff effects we find that discrimination yields higher standards than mfn and free trade independently of the extent of pollution spillovers when pollution is local and incentives to free ride on other countries abatement efforts are weak we show however that welfare is larger under mfn than under discrimination in a dynamic setting we consider the impact of symmetric and asymmetric treatments on the sustainability of an international environmental agreement iea and obtain that multilateral cooperation is easier to sustain under discrimination than under mfn or free trade

public trust and government betrayal abstract this study presents a simple model of government reputation in which government type cannot be directly observed by households with the variation that government type rather than being permanent follows an exogenous markov process this formulation captures three characteristics of bad policy outcomes governments which betray public trust do so erratically public trust is regained only gradually after a betrayal and governments with recent betrayals betray with higher probability than other governments

credit rating industry a helicopter tour of stylized facts and recent theories the recent subprime crisis and the ongoing euro zone crisis have generated an enormous interest in the credit rating industry not only among economists but also among average citizens as a consequence we have seen an explosion of the economic literature on the industry the objective of this survey is to introduce readers to the key stylized facts of the credit rating industry and to the recent theoretical economic literature on this industry

conflicts of interest information provision and competition in the financial services industry abstract in some markets sellers have better information than buyers over which products best serve a buyer s needs depending on the market structure this may lead to conflicts of interest in the provision of information by sellers this paper studies this issue in the market for financial services the analysis presents a new model of competition between banks where price competition influences the ensuing incentives for truthful information revelation we also compare conflicts of interest in two different firm structures specialized banking and one stop banking

competitive bluffing an examination of a common practice and its relationship with performance bluffing a common and consequential form of competitive behavior has been comparably ignored in the management literature even though misleading one s rivals is suggested to be an advantageous skill in a multifaceted and highly competitive environment to address this deficiency and advance scholarship on competitive dynamics our study investigates the moral reasoning behind competitive bluffing and using a simulated market entry game examines the performance effects of bluffing findings suggest that decision makers views on the ethicality of bluffing competitors differ from their beliefs on the ethicality of misleading other organizational stakeholders analysis also indicates that decision makers who view competitor bluffing as more ethical less unethical are more willing to engage in competitive bluffing finally while bluffing is often thought to be an effective business practice results show that in the context of repeated interaction bluffing is not conducive to high levels of performance and in fact can have undesirable consequences

information percolation momentum and reversal abstract we propose a joint theory of time series momentum and reversal based on a rational expectations model we show that a necessary condition for momentum to arise in this framework is that information flows at an increasing rate we focus on word of mouth communication as a mechanism that enforces this condition and generates short term momentum and long term reversal investors with heterogeneous trading strategies contrarian and momentum traders coexist in the marketplace although a significant proportion of investors are momentum traders momentum is not completely eliminated word of mouth communication spreads rumors and generates price run ups and reversals our theoretical predictions are in line with empirical findings

cheap talk in the classroom how biased grading at school explains gender differences in achievements career choices and wages in this paper i provide a theoretical explanation for the gender differences in education and on the labour market that are observed empirically in most oecd organisation for economic cooperation and development countries including the us within a cheap talk model of grading i show that biased grading in schools results in 1 boys outperforming girls in maths and sciences 2 boys having more top and more bottom achievers in maths and sciences than girls 3 girls outperforming boys in reading literacy 4 female graduates enrolling in university studies more often than male graduates 5 the predominance of female students in arts and humanities at the university 6 the predominance of male students in maths and sciences at the university and 7 the gender wage gap on the labour market for the highly educated copyright 2009 wiley blackwell

new like new or very good reputation and credibility we show that sellers may earn reputation for their ability to deliver high quality goods on average by honestly announcing the realised quality of items for sale every period as the expected revenue stream from continuing with honest communication increases with their ability high ability sellers remain honest while low ability sellers find it too costly and sometimes lie about quality for short term gain thus cheap talk communication facilitates the market s learning of a seller s ability and strengthens reputation effects we study this new reputation mechanism and the induced market dynamics first when sellers cannot restart with a new identity and then when they can we extend the analysis to various other situations such as voluntary refund and moral hazard

using privileged information to manipulate markets insiders gurus and credibility access to private information is shown to generate both the incentives and the ability to manipulate asset markets through strategically distorted announcements the fact that privileged information is noisy interferes with the public s attempts to learn whether such announcements are honest it allows opportunistic individuals to manipulate prices repeatedly without ever being fully found out this leads us to extend sobel s 1985 model of strategic communication to the case of noisy private signals our results show that when truthfulness is not easily verifiable restrictions on trading by insiders may be needed to preserve the integrity of information embodied in prices

lying for strategic advantage rational and boundedly rational misrepresentation of intentions starting from hendricks and mcafee s 2000 example of the allies decision to feint at calais and attack at normandy on d day this paper models misrepresentation of intentions to competitors or enemies allowing for the possibility of bounded strategic rationality and rational players responses to it yields a sensible account of lying via costless noiseless messages in many cases the model has generically unique pure strategy sequential equilibria in which rational players exploit boundedly rational players but are not themselves fooled in others the model has generically essentially unique mixed strategy sequential equilibria in which rational players strategies protect all players from exploitation