on the robustness of equilibrium refinements abstract the philosophy of equilibrium refinements is that the analyst if he knows things about the structure of the game can reject some nash equilibria as unreasonable the word know in the preceding sentence deserves special emphasis if in a fixed game the analyst can reject a particular equilibrium outcome but he cannot do so for games arbitrarily close by then he may have second thoughts about rejecting the outcome we consider several notions of distance between games and we characterize their implications for the robustness of equilibrium refinements

reciprocity and cooperation in repeated coordination games the principled player approach abstract two long lived players play a repeated coordination game i show the restrictions on players beliefs which imply that cooperation is optimal play journal of economic literature classification number d83

reputation and impermanent types i consider a version of the chain store game where the incumbent firm s type evolves according to a markov process with two states a tough type who always fights entry and a weak type who prefers to accommodate there exists a minimal level of persistence necessary for the incumbent to be able to sustain any reputation for being tough above that level as the number of markets t increases in equilibrium play alternates between intervals of entry by competitors and intervals of deterrence when t is infinite then regardless of the discount factor there exists a sequential equilibrium in which the incumbent s payoff is bounded below her stackelberg payoff both results are in contrast to the outcome when the incumbent s type is fixed one interpretation is that reputation is not permanent but must be renewed occasionally

reputation in dynamic games abstract we analyze reputation in a game between a large player and a continuum of long lived small players in which state variables affect players payoffs the large player s type is private information we give conditions under which in every nash equilibrium a very patient large player will get almost the largest payoff consistent with the small players choosing a best response in a large finite truncation of the game while our results apply to the time inconsistency problem of optimal government policy we show that for the durable goods monopoly reputation may fail to improve the monopolist s payoff journal of economic literatureclassification numbers c72 c73

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

defending against speculative attacks the policy maker s reputation abstract this paper studies how speculative attacks and regime change arise from the interaction between a policy maker s reputation for defending against speculative attacks and speculators learning of the policy maker s type if speculators receive conditionally independent and identically distributed private signals about the policy maker s type in every period then no matter how precise their per period private signals are there can be no equilibrium with attacks if the speculators receive private signals whose precision increases as a power function of the time with the power strictly greater than two there exist infinitely many equilibria with attacks but this equilibrium multiplicity arises from the timing of the attacks only in such a case the set of status quos surviving in any equilibrium is strictly larger than in the case of a short lived policy maker

money supply announcements and interest rates another view in this paper i use a new approach to analyze the impact of money supply announcements on the bond market before 1980 the only available work on this subject consisted of a few unpublished papers by conrad 1978 sivesind 1978 and urich 1979 1 more recently published papers by grossman 1981 and urich and wachtel 1981 have appeared roley 1982 extends the grossman study to incorporate data after the federal reserve policy statement of october 6 1979 both grossman and urich and wachtel are primarily concerned with the question of money market efficiency using survey data made available by money market services of san francisco and data on treasury bill yields each finds that the market responds quickly to unanticipated changes in the money supply but that anticipated changes have no effect on interest rates in addition grossman finds that when he adds other variables such as past changes in the money

reputation and experimentation in repeated games with two long run players this paper considers reputation effects in a repeated game between two long run players one of whom is relatively patient and may be committed to a fixed strategy which punishes the opponent for increasingly long periods whenever inappropriate actions are taken by following this commitment strategy the more patient player can induce a sufficiently patient opponent to experiment to see whether the commitment strategy is also being followed off the equilibrium path this can guarantee the more patient player in any nash equilibrium a payoff close to the highest feasible payoff consistent with the individual rationality of the other player for an arbitrary degree of patience of the less patient player a weaker result is established the more patient player is guaranteed an average equilibrium payoff close to the static stackelberg payoff this latter result generalizes that of schmidt 1993 who established the same result for the restricted class of games of conflicting interests

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

reputation and exogenous private learning abstract short run competitors in the chain store game receive noisy signals of the long run incumbent firm s type the history of signals which in the limit is fully revealing is observable to the competitors but possibly not to the incumbent as long as there is sufficient noise in the signals then in any equilibrium a patient weak incumbent obtains a payoff strictly higher than her minmax payoff

the response of short term interest rates to weekly money announcements each friday at 4 10 p m est the federal reserve announces its estimate of the narrowly defined money stock for the statement week ending nine days previously these money announcements have become one of the main events in financial markcts if for no other reason than the fact that significant movements in interest rates have been associated with large unanticipated changes in the money stock moreover since the late 1970s interest rate fluctuations in response to money stock announcements have dramatically increased over the 1l 2 hour intervals spanning the weekly announcements for example the variance of the change in the threemonth treasury bill yield in the three years since october 1979 is more than thirty times larger than that of the previous two year period l two factors may account for a large portion of the increased volatility of shortterm interest rates first on october 6 1979 the federal reserve adopted a reserve aggregate approach to monetary control replacing a procedure that emphasized stability of short term yields second despite the greater emphasis placed on monetary control the variance of weekly announced changes in the money stock has risen by about 70 percent since late 1979 in turn if greater volatility of announced changes makes future changes more difficult to predict the volatility of unanticipated weekly changes in money would have also increased 2 thus if financial markets are efficient and if weekly money announcements contain relevant information larger unanticipated changes in money may have caused larger fluctuations in interest rates

comparing time series and survey forecasts of weekly changes in money a methodological note measured as the difference between the announced change and the expected change derived from the money market services inc weekly survey of government securities dealers unlike other survey measures of expectations the most notable example of which is the livingston survey data these expectations are formed by active market participants consequently the survey s forecast made public before the fed s announcement of the actual change in the money stock is commonly thought to represent the market s expectation the concern in this paper is not with the impact of unanticipated money changes on nominal interest rates the purpose is to compare the relative forecasting abilities of the survey predictions and those obtained from a timeseries model this question is of interest because the weekly money series used in previous research includes certain abnormal weeks in which exogenous factors may significantly alter the series stochastic properties see for example cornell 1 urich and wachtel 9 thus the influence of these abnormal weeks weeks that include benchmark revisions changes in seasonal factors and weeks in which there is a social security effect is examined by comparing forecasting results for two samples one includes these weeks and the other deletes them following pearce 6 this approach allows us to test the hypothesis that the survey responses are at least weak form rational and to see how sensitive this test is to the sample of weeks used unlike previous studies we use two survey forecast series the median forecast made public prior to the announced change in ml and the mean series constructed from individual respondents forecasts zarnowitz s 10 examination of the asa nber survey forecasts indicates that the mean forecast is on average statistically superior to the median this finding is based on the idea that the mean forecast uses a more informationally diverse data set consequently it is

durable goods an explanation for their slow adjustment at the microeconomic level durable purchases are often discontinuous and relatively large this feature has the potential to explain why aggregate expenditure on durables responds only slowly relative to the frictionless permanent income model to wealth and other aggregate innovations in this paper i develop new results on the problem of dynamic aggregation of stochastically heterogeneous units which help to characterize the connection between microeconomic behavior and aggregate dynamics in the presence of nonconvex adjustment costs using these results and splitting postwar u s aggregate durable purchases into different subcategories and time periods i provide further support for the view that lumpy microeconomic purchases play an important role in explaining the time series behavior of aggregate expenditure on durable goods

optimal aggregation of money supply forecasts accuracy profitability and market efficiency we present a general procedure for aggregating expert forecasts which exploits regularities in the structure of information within the forecaster population specific information structures lead to aggregation methods which adjust for additive bias differences in individual accuracy and correlation among forecasts as an application we construct composite predictions of the weekly change in the money supply from forecasts made by twenty major securities dealers for which high positive correlation is found to be a significant characteristic due to instability in the information structure our methods cannot improve on the accuracy of a simple average in this case however they do capture information about the correlation among money supply forecasts which is not fully impounded in short term interest rates forecasts from our models accurately predict the direction of price changes for treasury bills and treasury bill futures after a money supply announcement the adjustment of prices to information in financial markets has been studied at length mostly from the perspective of the efficient markets hypothesis market efficiency tests typically look at the behavior of prices the end product

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

social security payments money supply announcements and interest rates abstract a monthly cycle existed in initially announced changes in seasonally adjusted m1 for a period extending at least from september 1977 to february 1984 this cycle was the source of systematic errors in the widely used money market services forecast of m1 such errors can induce a spurious relation between interest rates and expected changes in the money supply when the survey forecasts are corrected to eliminate systematic errors the apparent negative relation between interest rates and expected money supply changes disappears interest rates were not systematically related to either anticipated or unanticipated money supply changes during the period february 1984 to december 1986

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

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

on disclosure policy in contests with stochastic entry we study how a contest organizer who seeks to maximize participant effort should disclose the information on the actual number of contestants in an imperfectly discriminatory contest with stochastic entry when each potential contestant has a fixed probability of entering the contest the optimal disclosure policy depends crucially on the properties of the characteristic function h f f where f is the impact function the contest organizer prefers full disclosure full concealment if h is strictly concave strictly convex however the expected equilibrium effort is independent of the prevailing information disclosure policy if a linear h tullock contest applies

contract negotiation and the coase conjecture a strategic foundation for renegotiation proof contracts what does contract negotiation look like when some parties hold private information and negotiation frictions are negligible this paper analyzes this question and provides a foundation for renegotiation proof contracts in this environment the model extends the framework of the coase conjecture to situations in which the quantity or quality of the good is endogenously determined and to more general environments in which preferences are nonseparable in the traded goods as frictions become negligible all equilibria converge to a unique outcome which is separating efficient and straightforward to characterize

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

poundm3 surprises and asset prices in this paper the relationship between unanticipated sterling m3 m3 and a variety of asset prices is investigated for part of the uk s experience with monetary targeting the unanticipated component of monetary growth is generated using money market services uk survey data and an arima model it is demonstrated that the uk survey data are rational in that they are an unbiased and efficient forecast and that the market efficiently incorporates unanticipated money growth into asset prices the sign of the unanticipated monetary component in our asset price equations tends to indicate that the fisher the inflation expectations hypothesis is better supported during the sample period

market response to the weekly money supply announcements in the 1970s the hypothesis that the weekly announcement of the money supply affects interest rates is examined the announcement effect is interpreted as a policy anticipation effect that is an unanticipated increase in the money supply leads to an increase in interest rates in anticipation of future tightening by the federal reserve estimates of this effect with proxies for the unanticipated change constructed from a survey of money supply forecasts and an arima model indicate that a financial markets respond very quickly to the announcement and b the response was largest when policymakers emphasized the importance of the monetary aggregates financial market participants are careful observers of the weekly money supply announcement and generally agree that the announcement often leads to changes in interest rates this occurs because the announcement leads market participants to revise their expectations both of future federal reserve policy actions and of future economic conditions in this paper we examine the response of yields on treasury bills to the announcement of the money supply and the extent to which that response has varied in the last ten years money supply announcements may affect market interest rates in three ways first actual expansion of the money supply leads to lower interest rates through a liquidity effect however rapid monetary growth which is not anticipated leads market participants to expect the federal reserve to counteract such growth in the future as a consequence there may be a policy anticipation effect which causes higher interest rates in anticipation of future tightening furthermore prolonged rapid monetary growth also creates inflation and inflationary expectations which lead to higher interest rates thus there may exist a third effect the inflationary expectations effect which also leads to higher interest rates our interest in this paper is in the immediate market response to the weekly announcement of the money supply which as we argue below is most likely to be a policy anticipation effect the policy anticipation effect is best described by example suppose that the announced change in the money supply exceeds that which was expected by

a theory of trade policy leadership abstract this paper constructs a two country model of bilateral trade negotiations in the presence of political uncertainty to demonstrate that unilateral trade liberalization may be an optimal policy for a large country the political uncertainty is due to producer opposition to trade agreement ratification in the foreign country unilateral liberalization by the home country has a salutary effect on negotiations because it mitigates the pain of potential ratification failure on the foreign country it also promotes foreign ratification because it effectively punishes foreign import competing producers for lobbying against an agreement these benefits are shown to outweigh up to a point the terms of trade cost that the home country must suffer when it actually liberalizes unilaterally in equilibrium therefore we see a pattern in which the home country unilaterally liberalizes for several periods until ratification in the foreign country succeeds at which point foreign country finally reciprocates we also demonstrate that contrary to the standard optimal tariff result there may be an inverse relationship between the home country s monopoly power and its optimal unilateral tariff

is more information always better a case in credit markets this paper studies the impact of behavioral and non behavioral information contained in consumer credit reports on the credit market a repeated game of incomplete information between a borrower and a sequence of lenders is considered lenders beliefs regarding the borrower s type depend on the borrower s historical loan performance and other informative signals it is established that for low beliefs strategic defaults occur in equilibrium as the borrower defaults on his loans despite having the ability to repay them further as the ancillary signals become increasingly informative of the borrower s type the range of beliefs over which strategic defaults occur expands this increase in strategic defaults highlights an unintended negative effect of allowing informative signals to influence beliefs on the upside the informative signals allow lenders to learn the borrower s type more quickly

switching costs in frequently repeated games abstract we add small costs of changing actions and frequent repetition to finitely repeated games making some surprising commitments credible naturally switching costs make it credible not to change action however this can occur for small switching costs and gives a unique subgame perfect equilibrium in coordination games when pareto dominance and risk dominance coincide in the prisoners dilemma switching costs reduce the incentive to deviate from mutual cooperation but reduce the incentive to switch from cooperation to punish defection hence whether switching costs enable cooperation depends on which effect dominates switching costs can make complex threats credible enabling a player to earn more than his stackelberg payoff journal of economic literature classification numbers c7 c73

merging reputation and repeated games with incomplete information we relate and unify several results that appeared in the following domains merging of probabilities perturbed games and reputation phenomena and repeated games with incomplete information journal of economic literature classification numbers c72 d83

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

on the role of outside options in bargaining with obstinate parties the presence of obstinate types in bargaining has been shown to alter dramatically the bargaining equilibrium strategies and outcomes this paper shows that outside options may cancel out the effect of obstinacy in bargaining when parties have access to stationary outside options we show that when opting out is preferable to accepting the inflexible demand of the other party there is a unique perfect bayesian equilibrium in which each party reveals himself as rational as soon as possible a similar conclusion holds when outside options may only be available at a later date or when only one party has access to an outside option

bargaining reputation and equilibrium selection in repeated games with contracts consider a two person intertemporal bargaining problem in which players choose actions and offers each period and collect payoffs as a function of that period s actions while bargaining proceeds this can alternatively be viewed as an infinitely repeated game wherein players can offer one another enforceable contracts that govern play for the rest of the game theory is silent with regard to how the surplus is likely to be split because a folk theorem applies perturbing such a game with a rich set of behavioral types for each player yields a specific asymptotic prediction for how the surplus will be divided as the perturbation probabilities approach zero behavioral types may follow nonstationary strategies and respond to the opponent s play in equilibrium rational players initially choose a behavioral type to imitate and a war of attrition ensues how much should a player try to get and how should she behave while waiting for the resolution of bargaining in both respects she should build her strategy around the advice given by the nash bargaining with threats nbwt theory developed for two stage games in any perfect bayesian equilibrium she can guarantee herself virtually her nbwt payoff by imitating a behavioral type with the following simple strategy in every period ask for and accept nothing less than that player s nbwt share and while waiting for the other side to concede take the action nash recommends as a threat in his two stage game the results suggest that there are forces at work in some dynamic games that favor certain payoffs over all others this is in stark contrast to the classic folk theorems to the further folk theorems established for repeated games with two sided reputational perturbations and to the permissive results obtained in the literature on bargaining with payoffs as you go

value of reputation in the chain store game with multiple incumbents abstract we extend the basic chain store game to the two incumbent case a highly stylized model is developed to analyze incentives of incumbent firms to maintain reputation for toughness entry deterrence has a public good property since maintaining reputation is costly each incumbent has an incentive to free ride on the entry deterring activities of its counterpart as a result of these incentives both incumbents accommodate when they both have a relatively high initial reputation for toughness this extreme form of underinvestment in entry deterrence becomes less likely as the number of markets with potential entry increases we also demonstrate that an incumbent s payoff is a decreasing function of its reputation over a large range of parameters this result stands in sharp contrast to the existing versions of the chain store game where high reputation for toughness always benefits a weak incumbent

reputation and equilibrium selection in games with a patient player a single long run player plays a simultaneous move stage game against a sequence of opponents who play only once but observe all previous play let the stackelberg strategy be the pure strategy to which the long run player would most like to commit himself if there is positive prior probability that the long run player will always play the stackelberg strategy then his payoff in any nash equilibrium exceeds a bound that converges to the stackelberg payoff as his discount factor approaches one when the stage game is not simultaneous move this result must be modified to account for the possibility that distinct strategies of the long run player are observationally equivalent

railroad rate deregulation and uncertainly of farm level prices for corn uncertainty of country elevator prices for corn in terms of error variance and mean squared forecast errors failed to increase in response to the deregulation in 1980 of railroad rates regression analysis was used to separate the uncertainty impacts of deregulation from those of other unanticipated changes in supply and demand factors influencing uncertainty included unexpected changes in storage costs export demand corn futures and rail car utilization some of the factors creating price uncertainty prior to deregulation were replaced by new uncertainty factors occurring as a result of deregulation

stationarity rationalizability and bargaining strategies for the seller and the buyer which are weakly stationary we demonstrate that any initial offer from the seller induced by a strategy rationalized by a weakly stationary acceptance rule for the buyer must entail the coase property our result does not presume the selection of a particular equilibrium and follows directly from the weak stationarity assumption of the buyer s acceptance rule and the rational behaviour of the players

the information content of weekly money supply announcements this paper analyzes the information content of weekly money supply announcements and the use of this information in the market determination of interest rates a short term rational expectations model of the financial market is constructed which incorporates the reaction of the federal reserve to deviations from target money supply and provides a context for analyzing the impact of announcements in the model the federal reserve attempts to maintain target growth rates in the money supply by compensating for past deviations from target announcements which contain an unanticipated movement in the money supply lead the public to expect that the federal reserve will change the rate of growth in the short run to compensate the revision of expectations about future short term money supply leads the public to revise their expectations about short term interest rates the implications of the model are empirically tested using data from a survey of expected changes in the money supply and u s treasury bill data the results support the implications of the model that is weekly money supply announcements do contain new information for the market determination of interest rates and it is only the unanticipated component of the announcement which is important

the life cycle of regulatory agencies dynamic capture and transaction costs the dynamics of regulation is analysed in a model where regulatory capture comes from the repeated interaction between an interest group and a regulatory agency regulatory institutions offer a framework for this dynamic process they put constraints on the interest group s influence the dynamics of regulation and its long run outcome depend on the political principal s the regulator s and the regulated firm s time preferences and their information some foundations for the transaction costs of side contracting used in the standard literature on collusion are provided those transaction costs are linked to the precise nature of regulatory institutions