efficient and durable decision rules with incomplete information we compare six concepts of efficiency for economies with incomplete information depending on the stage at which individuals welfare is evaluated and on whether incentive constraints are recognized an example is shown in which an incentive efficient decision rule may be unanimously rejected by the individuals in the economy we define durable decision rules which can resist such unanimous rejection and show that efficient durable decision rules exist

efficient mechanisms for bilateral trading we consider bargaining problems between one buyer and one seller for a single object the seller s valuation and the buyer s valuation for the object are assumed to be independent random variables and each individual s valuation is unknown to the other we characterize the set of allocation mechanisms that are bayesian incentive compatible and individually rational and show the general impossibility of ex post efficient mechanisms without outside subsidies for a wide class of problems we show how to compute mechanisms that maximize expected total gains from trade and mechanisms that can maximize a broker s expected profit journal of economic literature classification number 026

the role of net foreign assets in a new keynesian small open economy model abstract this paper develops a small open economy sticky price model that determines a unique stable long run asset position for households as function of their incentive to anticipate or postpone consumption and labor effort across periods this is accomplished by adopting an overlapping generations structure in which new households with no assets enter the economy in each period the same characteristics of household behavior that determine long run assets are also important determinants of the model s responses to shocks stabilizing producer prices results in a milder recession following a drop in world demand than stabilizing consumer prices because it prevents the markup in the pricing of goods from increasing in addition given an initial foreign debt allowing consumer prices to rise causes a decrease in the ex post real interest rate on impact lowering the interest burden of the initial debt the differences across policy rules generated by the initial asset position are robust to changes in the latter as long as these are brought about by changes in parameter values that do not alter the fundamental characteristics of household and firm behavior that are also the key determinants of long run assets

bargaining on behalf of a constituency abstract we study bargaining situations in which one side consists of a group of people who elect a representative to bargain with another party on their behalf a two phase bargaining model is developed in which a principal agent problem between the constituency and its representative is embedded with a natural refinement of sequential equilibrium we characterize the set of equilibria and examine its efficiency properties we show that agency problems in the delegation relationship rather than asymmetric information between the two bargainers can cause severe bargaining inefficiency i e delay in reaching agreements extensions of the model and applications to union firm bargaining are then discussed briefly journal of economic literature classification numbers c78 d82 j52

exchange rate policies and endogenous time preference a dynamic analysis of a small open economy abstract the effects of exchange rate policies are examined for a small open economy with endogenous rate of time preference using optimizing framework and introducing money into the utility function it is shown that a depreciation of the domestic currency generates a surplus in the current account it also leads to an increase in consumption and a decrease in the holdings of real balances in the long run

audience costs and the dynamics of war and peace we estimate audience costs and examine their substantive effects on the evolution of interstate disputes by using an infinitely repeated and dynamic game of crisis escalation unlike past efforts our approach estimates country specific audience cost parameters without relying on proxy variables such as democracy measures contrary to intuition increases in a country s audience costs encourage it to initiate disputes in equilibrium because the costs serve as a commitment device during the subsequent crisis incentivizing the country to stand firm and coercing its opponent to back down nonetheless the results demonstrate that larger audience costs would result in more peace worldwide as they also discourage potential opponents from initiating disputes beyond regime type we find that a free press provisions for executive appointment or removal and historical rivalries are also important determinants of audience costs

a neoclassical model of the balance of payments this paper analyses the transitory and long run effects of devaluation and tariffs as well as the effects of alterations in the domestic money supply and the terms of trade for a small country on fixed exchange rates these issues are investigated in a self contained dynamic optimization model of the sort popularized by brock 1974 1975 familiar results in the trade literature are thereby explicated for the nonspecialist who is nonetheless familiar with brock s work there are some new results regarding the role played by income and substitution effects in determining the consequences of terms of trade shifts this paper introduces a perfect foresight optimizing model of the monetary approach to the balance of payments for a small country on fixed exchange rates the model is then used to analyse the effects on the balance of payments of devaluation of a tariff and of changes in the terms of trade the effects of devaluation tariffs and changes in the terms of trade have been analysed previously within the framework of nonoptimizing models dornbusch 1973 1980 and anderson and takayama 1977 have studied the effect of devaluation mussa 1974 1976 anderson and takayama 1978 1981 and batra and ramachandran 1980 have studied the effect of tariffs and rodriguez 1976 batra and ramachandran 1980 and anderson and takayama 1981 have studied the effect of changes in the terms of trade optimizing models in which real balances appear as an argument in the utility function are increasingly popular in international economics the general approach was inspired by sidrauski 1967 and brock 1974 1975 recent contributions to the trade literature using this framework include dornbusch and mussa 1975 calvo 1980 1981 liviatan 1981 and obstfeld 1981 a 1981 b 1982 the purpose of this paper is to translate the conventional small country fixed exchange rate model into this framework the results are generally congruent with those in the nonoptimizing literature which suggests that the money in the utility function approach works well here compared to the nonoptimizing literature the real advance is that price adjustment and price expectations are endogenous and rational among the benefits are that one need not postulate the ad hoc price adjustment mechanism used by anderson and takayama nor the backward looking and hence irrational permanent income formulation used by rodriguez furthermore there has been controversy over the balance of payments effects of a shift in the terms of trade while the model s predictions on this issue are theoretically ambiguous the model shows that the answer depends crucially on the magnitude of income effects this clarifies the conditions required for a terms of trade shift to improve or worsen the balance of payments

the dollarization of a small economy within a utility maximizing framework we study the effects of replacing the national currency with the dollar in a small open economy the impact effect is a drop in the levels of liquidity and wealth the economy reaccumulates real balances by reducing consumption and showing a trade surplus the welfare implications of the program depend on the social rate of time preference and the inflation rate differential we show that the u s can improve both its own welfare and that of the small country s by bribing it into switching currencies we study how these results change with the introduction of capital mobility

whose opinion counts implementation by sortition abstract sortition is the process of selecting decision makers or senators by a lottery we introduce sortition in implementation theory by augmenting a mechanism with a kleroterion or lottery machine p that selects the senators an outcome is implemented after consulting only the opinions of the senators we call the corresponding notion of implementation as p implementation and provide necessary and sufficient conditions for p implementation our main result is that in economic environments every nash implementable social choice rule scr is also p implementable if p selects every quartet of players with positive probability and always selects at least three senators we apply this result to two kleroteria oligarchic democracy and random sampling in economic environments every nash implementable scr can be implemented by oligarchic democracy of three oligarchs in economic environments every nash implementable scr can be implemented by randomly selecting four senators

efficient secrecy public versus private threats in crisis diplomacy this paper explores when and why private communication works in crisis diplomacy conventional audience cost models suggest that state leaders must go public to reveal information in interstate crises because leaders cannot enhance their credibility by tying their hands if domestic audiences cannot observe their private signals i present a crisis bargaining game where both the sender and the receiver of signals have a domestic audience the equilibrium analysis demonstrates that a private threat albeit of limited credibility can be equally compelling as a fully credible public threat secrecy works in crisis diplomacy despite its informational ine cacy because secrecy insulates leaders from domestic political consequences when they capitulate to a challenge to avoid risking unwarranted war the logic of e cient secrecy may shed light on the unaccounted history of private diplomacy in international crises the alaska boundary dispute illustrates this logic

the effectiveness of exchange rate changes this article addresses the question of whether exchange rates are a useful policy instrument the very question will raise tempers the suggestion that the real exchange rate is a policy variable is firmly rejected by any student in the new classical tradi tion and even by a broader group who are reluctant to declare a broad policy role for the nominal quantity of money or the nominal exchange rate either can of course be manipulated but whether there is scope to change in this manner the real quantity of money or the real exchange rate is quite another matter

implementation in weakly undominated strategies optimality of second price auction and posted price mechanism we study the mechanism design problem of guaranteeing desirable performances whenever agents are rational in the sense of not playing weakly dominated strategies we first provide an upper bound for the best performance we can guarantee among all feasible mechanisms the bound is represented as the maximized value of the designer s objective subject to the inequality version of the standard envelope incentive conditions we then prove the bound to be tight under certain conditions on the designer s prior over the agents pay off types in auction and bilateral trade applications in private value auction and bilateral trade the optimal mechanisms a second price auction and posted price mechanism respectively satisfy dominant strategy incentive compatibility the classical notion of robust mechanisms in an interdependent value auction we find that a second price auction is optimal in revenue with interdependent values which is neither dominant strategy nor ex post incentive compatible but satisfies the novel incentive compatibility introduced in this analysis

full implementation and belief restrictions we introduce a framework to study the problem of full implementation under general restrictions on agents beliefs which we call implementation first we provide a characterization of the properties of the mechanisms that achieve implementation these conditions relate the possibility of achieving full implementation to the strength of the strategic externalities induced by the mechanism we then study how to achieve full implementation via the design of simple transfer schemes in these context the general conditions for implementation suggest a simple design principle in which belief restrictions are used to weaken the strategic externalities induced by the baseline transfers of the belief free benchmark importantly our results require minimal information on agents beliefs which regard simple moments of the distribution of types these moment conditions arise naturally in applications and in practical problems of mechanism design

integer game with delay in this note we study a version of a war of attrition in which the players pick delays and the player with the longest delay wins unlike the war of attrition all players have to experience the longest delay before the consumption takes place we show that the game has no mixed strategy nash equilibria the game can be seen as a re interpretation of the integer game which is one of the most important and most criticized constructions in the full implementation literature unlike the integer game it has a well defined best response against any mixed strategy

coalition proof implementation abstract a new condition is shown to be necessary and sufficient for coalition proof nash equilibrium cpne implementation in environments with complete information this result implies that all choice functions are cpne implementable when individuals utility functions are bounded with respect to all variables except for money and are either analytic or quasi linear journal economic literature classification numbers c72 d72 d78

cheap talk and burned money we augment the standard crawford sobel 1982 econometrica 50 1431 1451 model of cheap talk communication by allowing the informed party to use both costless and costly messages the issues on which we focus are the consequences for cheap talk signaling of the option to burn money and the circumstances under which both cheap talk and burned money are used to signal information

real asset returns inflation and activity in a small open cash in advance economy abstract the effects of inflation are worked out for a small open economy with cash in advance cia constraints on bond purchases if all transactions are subject to cia constraints an increase in the inflation rate will reduce savings bringing about a current account deficit while the capital stock will be unaffected if investment is not subject to cia constraints an increase in the inflation rate will encourage investment and reduce savings bringing about a current account deficit numerical evaluation of the model gives rise to falls in real interest rates that are in line with recent empirical findings

military coercion in interstate crises in an international crisis states make demands backed by threats to use force although these threats can be explicit in diplomatic communications they will not generally carry much weight unless substantiated by some show of force military measures designed to convey the commitment to resort to arms if one s demands are not satisfactorily met to have an impact this commitment must be credible it must be in one s interest to carry out the threat if the opponent refuses to comply in an environment where states possess private information about their valuations capabilities or costs credibility can be established by actions that a state unwilling to fight would not want or would not dare to take military moves such as arms buildups troop mobilizations and deployments to the potential zone of operations can alter incentives in a crisis by changing one s expected payoff from the use of force these are tacit bargaining moves that can restructure the strategic context thereby creating and possibly signaling one s commitments while undermining those of the opponent how can states use the military instrument to establish commitments and how does the nature of the instrument affect their ability to communicate them credibly to their adversaries there are two distinct mechanisms for credible signaling in economic models information can be transmitted reliably by sinking costs actors burn money to reveal that they value the disputed issue even more in contrast theories of interstate crisis bargaining usually rely on choices that increase the difference between backing down and fighting actors tie their hands by running higher risks of war to reveal their resolve the first mechanism involves costs that actors pay regardless of outcome and the second involves costs that actors pay only if they fail to carry out some threat or promise

cheap talk with two audiences these problems have in common a simple structure an informed sender says something to two interested but uninformed receivers who then take actions based on their beliefs these actions affect the sender as well as the receivers in this paper we study how costless nonverifiable claims cheap talk can affect these beliefs and hence the actions and how the incentives for truthful revelation to one receiver are affected by the presence of the other we then ask how welfare is affected by whether claims are made in public or in private as some of the above examples suggest public messages may be more credible than private messages addressed to either audience one possibility is that the presence of one audience can discipline the sender s relationship with the other we call this one sided

crawling peg inflation hedges and exchange rate dynamics this paper stresses the effects of currency substitution and speculation on inflation hedges on the relative price of home goods in the two sector general equilibrium portfolio balance model examining the overshooting hypothesis of exchange rates in association with the overshooting phenomenon of price of inflation hedges it has shown that exchange rate undershooting is plausible with the significant overshooting of the price of inflation hedges when domestic residents hold only domestic money and inflation hedges however the impact of currency substitution is strong enough to lead to exchange rate overshooting if the domestic residents have access to foreign currency

the capital inflows problem revisited a stylized model of southern cone disinflation in the late 1970s countries in latin america s southern cone initiated attempts to lower domestic inflation rates through the progressive reduction of a preannounced rate of exchange rate devaluation the stabilization programs gave rise to massive capital inflows real exchange rate appreciation and current account deficits this paper develops a stylized intertemporal framework in which the effects of a credible preannounced disinflation scheme can be studied it is shown that even when agents have perfect foresight and markets clear continuously the capital inflows phenomenon and the associated real appreciation may result while unanticipated permanent inflation changes are neutral in the paper anticipated inflation is neutral only in exceptional circumstances a preannounced disinflation operates by altering the path of an expenditure based real domestic interest rate that depends on expected changes in the prices of liquidity services and nontradable consumption goods

on the outcome of inconsistent programs under exchange rate and monetary rules abstract this paper studies the case of inconsistent programs of monetary policy that is programs incompatible in the long run with a given budget deficit so that at some point in the future there is an eventual crisis and demise of the program all of which is from the outset anticipated by the public the context is one of a small open economy with perfect foresight in which two sets of possibilities are analyzed i a monetary or an exchange rule for the conduct of monetary policy and ii presence or absence of capital mobility it is found that while the choice of the rule is unimportant restrictions on capital mobility determine a very different response for the case of either rule concerning side effects of the program on non monetary variables and on the post crisis level of country indebtedness

monetary policy in a small open economy with durable goods and differing cash in advance constraints abstract we consider the effects of inflation in a small open economy when expenditures on non durables are more heavily financed with money than expenditures on durables the distinctions between non durables and durables and asymmetric cash in advance constraints give rise to important dynamics

dynamics of the exchange rate in anticipation of pegging abstract this paper studies an economy in which agents expect the current floating rate regime to be interrupted on a specific future date by a transitional fixed rate policy when the new peg is not revealed in advance the path of the floating rate in anticipation of pegging is determined by the interaction between what agents perceive to be the objectives and the constraints of the central bank the paper highlights the role of the pegging date the duration of the fixed rate interval the quantity of reserves available to the authorities and the nature of policies expected after pegging is terminated

balance of payments dynamics and exchange rate management abstract this paper studies the dynamics of the balance of payments in response to policy disturbances under the assumption that the central bank devalues the country s currency over time at a constant pre announced rate depending on the magnitudes of the parameters of the model i find that a given disturbance may result in qualitatively different short run behavior of the balance of payments accounts in each case however the adjustment process will lead the economy to a stable long run equilibrium provided the government finances its spending according to a certain set of rules

domestic opposition and signaling in international crises this article explores the effect of domestic political competition on the escalation of international crises it combines an incomplete information model of crisis bargaining with a simple model of two party electoral choice one state has two strategic actors a government and an opposition party both of which declare openly whether they support the use of force to alter the status quo the rival state updates its beliefs and selects its strategy in response to both signals the parties payoffs depend upon a retrospective evaluation by the domestic electorate the model shows that the inclusion of a strategic opposition party decreases the ex ante probability of war by helping to reveal information about the state s preferences this finding has important implications for research on democracy and international conflict since it suggests a mechanism through which democratic states can overcome informational asymmetries which have been identified as a central obstacle to negotiation

how many hands to make sanctions work comparing eu and us sanctioning efforts abstract one of the core disputes in the literature on economic statecraft addresses the conditions under which multilateral sanctions are more successful than unilateral ones our game theoretic model implies that extant assessments do not sufficiently differentiate between the varying abilities of multilateral and unilateral senders in credibly threatening and carrying out sanctions we introduce a selection argument that focuses on the complex decision making process of the european union eu to impose sanctions in comparison to the united states us the institutional structure of the eu and conflicting economic interests of multiple principals make the imposition of sanctions much more difficult in addition the international organization is less accountable vis a vis the voters both mechanisms render sanction threats by the eu less credible since the united states as a unilateral sender can issue more credible sanction threats imposed us sanctions are a negative selection of cases and thus less successful than restrictive measures imposed by the eu we test these propositions with a new dataset on threatened and imposed sanctions by the european union and the united states for the period between 1989 and 2015 the empirical evidence demonstrates that eu sanctions are indeed more successful than those by the us in contrast us sanction threats are more successful than those by the eu we provide evidence for the difficulties of multilateral senders to impose sanctions by showing that eu sanctions are both less likely and less severe the more varied the economic links of the multilateral sender with the sanctioned state are

uniform commercial policy illegal trade and the real exchange rates a theoretical analysis countries on fixed exchange rates sometimes use uniform tariff cum subsidy utcs schemes as a way of achieving a real depreciation without disturbing the nominal exchange rate a potential drawback of this policy in relation to an across the board devaluation is that a utcs scheme provides incentives for illegal trade using an optimizing model with currency convertibility and illegal trade the author finds that welfare is lower under a utcs scheme than under a corresponding across the board devaluation and that in some cases the real exchange rate actually appreciates in response to an increase in the utcs rate

a natural mechanism to choose the deserving winner when the jury is made up of all contestants abstract we analyze the problem of a jury choosing the winner from a set of agents when the identity of the deserving winner is common knowledge amongst the jurors but each juror is biased in favor of one different agent we propose a simple and natural mechanism that implements the socially optimal rule the winner is the deserving winner in subgame perfect equilibria

subgame perfect implementation of bargaining solutions abstract this paper provides simple four stage game forms that fully implement a large class of two person bargaining solutions in subgame perfect equilibrium the solutions that can be implemented by our game forms are those that maximize a monotonic and quasi concave function of utilities after normalizing each agent s utility function so that the maximum utility is 1 and the utility of the disagreement outcome is 0 this class of solutions includes the nash kalai smorodinsky and relative utilitarian solutions the game forms have a structure of alternating offers and contain no integer device

rationalist explanations for war realist and other scholars commonly hold that rationally led states can and sometimes do fight when no peaceful bargains exist that both would prefer to war against this view i show that under very broad conditions there will exist negotiated settlements that genuinely rational states would mutually prefer to a risky and costly fight popular rationalist and realist explanations for war fail either to address or to explain adequately what would prevent leaders from locating a less costly bargain essentially just two mechanisms can resolve this puzzle on strictly rationalist terms the first turns on the fact that states have both private information about capabilities and resolve and the incentive to misrepresent it the second turns on the fact that in specific strategic contexts states may be unable credibly to commit to uphold a mutually preferable bargain historical examples suggest that both mechanisms are empirically plausible

currency trade and capital flows in general equilibrium this paper studies currency trade and capital flows in a one good general equilibrium exchange model with utility maximizing individuals the effects of both monetary and endowment shocks are examined it is shown that both can cause trade and capital flows the model is a two country version of the twostate optimizing model used recently by leroy 1984a 1984b to study the effects of monetary and endowment shocks in a closed economy each country issues its own currency real and nominal bonds and equity shares each receives an endowment of a perishable consumption good the demand for money is generated by entering real balances into the utility function as in dornbusch and mussa 1975 calvo 1981 liviatan 1981 obstfeld 1981a 1981b 1982 razin 1981 stockman 1983 and michener 1984 each country holds both currencies an assumption made only by liviatan both monetary growth and endowments of the consumption

coordination and discrimination in contracting with externalities divide and conquer abstract the paper studies bilateral contracting between n agents and one principal whose trade with each agent generates externalities on other agents it examines the effects of prohibiting the principal from i coordinating agents on her preferred equilibrium and ii making different contracts available to different agents these effects depend on whether an agent is more or less eager to trade when others trade more the prohibitions reduce the aggregate trade in the former case and have little or no effect in the latter case the inefficiencies under different contracting regimes are linked to the sign of the relevant externalities and are shown to be typically reduced by both prohibitions

efficient repeated implementation this paper examines repeated implementation of a social choice function scf with innitely lived agents whose preferences are determined randomly in each period an scf is repeated implementable in nash equilibrium if there exists a sequence of possibly history dependent mechanisms such that i its nash equilibrium set is non empty and ii every nash equilibrium outcome corresponds to the desired social choice at every possible history of past play and realizations of uncertainty we show with minor qualications that in the complete information environment an scf is repeated implementable in nash equilibrium if and only if it is ecient we also discuss several extensions of our analysis including constructions employing only nite mechanisms

monetary policy under dual exchange rates abstract this paper finds that the introduction of dual exchange rates gives the monetary authority greater independence from external constraints than it would otherwise enjoy the monetary authority is able to influence the level of aggregate demand in the short run and to sterilize the effects of temporary foreign disturbances in addition the paper finds that dual rates insulate the domestic economy fully from foreign interest rate changes but do not provide insulation from speculative disturbances

capabilities uncertainty and resolve a limited information model of crisis bargaining this paper presents and solves a crisis bargaining game under limited information the sides alternate offers from three possible offers with war and its costs starting if the target s counteroffer is rejected the equilibrium of the model falls into four different cases these four cases are analyzed to determine how the sides communicate through their offers and how the costs of war initial beliefs misperceptions and distribution of capabilities drive the probabilities of a crisis and war the model demonstrates a joint selection bias misspecification problem in empirical studies of crises arising from the unobservable nature of beliefs several empirical studies of crisis bargaining are discussed in the light of this methodological problem new patterns of evidence are found that support the presence of the selection problem and their conclusions are reexamined

implementation in undominated strategies a look at bounded mechanisms this paper examines the impact of placing natural restrictions on the mechanisms considered for implementation problems it is shown that if all mechanisms are considered and preferences satisfy a basic condition then any social choice correspondence can be implemented in undominated strategies an example points out that the strength of this result derives from the use of mechanisms with questionable features in part of the message space the agent who announces the highest integer is rewarded this sort of tail chasing construction common in the constructive proofs of the literature is used to assure that undesired strategy combinations do not form an equilibrium if such mechanisms are ruled out then the social choice correspondences which can be implemented in undominated strategies satisfy an incentive compatibility type condition called strategy resistence for social choice functions this is equivalent to strategy proofness this contrast suggests that this issue should be examined as it applies to other solution concepts used in implementation theory the last portion of the paper begins to explore the issue as it relates to nash implementation and undominated nash implementation

capital mobility and devaluation in an optimizing model with rational expectations this paper examines the effects of ex change rate policies when individuals maximize lifetime utility on the basis of rational expectations about the future the economy studied is one in which the authorities allow free mobility of capital under a crawling peg exchange rate regime many industrializing economies have adopted a crawling peg as a means of reconciling disparate inflation rates at home and abroad and some recent efforts to use the rate of crawl as an instrument of anti inflation policy have attracted considerable interest see carlos diaz alejandro tools similar to those employed here have been applied by guillermo calvo forthcoming to study this type of exchange rate management under conditions of capital immobility this abstract was borrowed from another version of this item

implementing coordinated team play abstract this note studies a moral hazard model of joint production in which there are strong gains to coordination the mechanism we propose for resolving the tacit collusion problem that arises in our setting makes use of at will contracts which provide the agents with the option to quit at any time journal of economic literature classification numbers c72 d82

complexity and repeated implementation this paper examines the problem of repeatedly implementing an ecient social choice function when the agents preferences evolve randomly we show that the freedom to set dierent mechanisms at dierent histories can give the planner an additional leverage to deter undesirable behavior even if the mechanisms are restricted to be simple and nite specically we construct a history dependent sequence of simple mechanisms such that with minor qualications every pure subgame perfect equilibrium delivers the correct social choice at every history while every mixed equilibrium is strictly pareto dominated more importantly when faced with agents with a preference for less complex strategies at the margin the ecient social choice function can be repeatedly implemented in subgame perfect equilibrium in pure or mixed strategies our results demonstrate a positive role for complexity considerations in mechanism design

an experiment on nash implementation we perform an experimental test of a modification of the controversial canonical mechanism for nash implementation using three subjects in non repeated groups as well as three outcomes states of nature and integer choices we find that this mechanism successfully implements the desired outcome a large majority of the time providing empirical evidence for the feasibility of such implementation in addition the performance is further improved by imposing a fine on a dissident so that the mechanism implements strict nash equilibria while our environment is stylized our results offer hope that experiments can identify reasonable features for practical implementation mechanisms

on the employment investment and current account effects of inflation abstract the effects of inflation targets are examined for a small open economy with cash in advance constraints an increase in the inflation rate by increasing the price of consumption relative to leisure reduces consumption and labor supply the fall in labor reduces the marginal productivity of capital and a fall in investment the country runs a current account surplus despite the fall in output the dynamics of the model for permanent and temporary policy changes are fully worked out with the aid of a diagrammatic apparatus quantitative analysis of the model reveals substantial impact and steady state effects

the optimal design of a market we study the optimal design of the rules of trade in a two period market given that agents arrive at different times and may only trade with agents present contemporaneously first period agents face a fixed cost of trading across periods given the non convexities associated with the fixed cost competitive trading rules can result in inefficiencies in such a market and anonymity must be sacrificed to achieve efficiency efficient trading rules have a market maker who is given a monopoly right to trade across periods who faces some competition within period trading but not across periods the efficient choice of who should be market maker can be made by auctioning rights to this position with uncertainty across periods efficient mechanisms may involve multiple market makers and the optimal number of market makers depends on the cost of trading level of risk aversion and presence of asymmetric information journal of economic literature classification numbers d40 d78 g10

nash equilibrium and welfare optimality if is a set of social alternatives a social choice rule scr assigns a subset of a to each potential profile of individuals preferences over a where the subset is interpreted as the set of welfare optima a game form or mechanism implements the social choice rule if for any potential profile of preferences 1 any welfare optimum can arise as a nash equilibrium of the game form implying in particular that a nash equilibrium exists and 2 all nash equilibria are welfare optimal the main result of this paper establishes that any scr that satisfies two properties monotonicity and no veto power can be implemented by a game form if there are three or more individuals the proof is constructive

implementation in minimax regret equilibrium this note studies the problem of implementing social choice correspondences in environments where individuals have doubts about the rationality of their opponents we postulate the concept of minimax regret as our solution concept and show that social choice correspondences that are maskin monotonic and satisfy the no veto power condition are implementable in minimax regret equilibrium for all 0 1