undominated coalition proof nash equilibria in quasi supermodular games with monotonic externalities abstract i introduce an undominated coalition proof nash equilibrium that is unique and is able to select undominated nash equilibria in a quasi supermodular game with a strict single crossing property and monotonic externalities

learning and wage dynamics we develop a dynamic model of learning about worker ability in a competitive labor market the model produces three testable implications regarding wage dynamics 1 although the role of schooling in the labor market s inference process declines as performance observations accumulate the estimated effect of schooling on the level of wages is independent of labor market experience 2 timeinvariant variables correlated with ability but unobserved by employers such as certain test scores are increasingly correlated with wages as experience increases and 3 wage residuals are a martingale we present evidence from the nlsy that is broadly consistent with the model s predictions

budget deficits stability and the monetary dynamics of hyperinflation hyperinflationary processes usually occur in countries with extremely large budget deficits in models of inflationary finance with rational expectations e g buiter 1987 large budget deficits cannot lead to hyperinflation the purpose of this paper is to reconcile the standard theoretical model with the stylized facts it shows that by introducing a lag in the adjustment of the money market into the standard inflationary finance model large budget deficits are indeed the main reason for hyperinflation the paper also provides an explanation for the ineffectiveness of moderate reductions in the deficit in reducing inflation and argues that fiscal lags can be destabilizing copyright 1989 by ohio state university press

banking in computable general equilibrium economies abstract in this paper we develop a computable general equilibrium economy that models the banking sector explicitly banks intermediate between households and between the household sector and the government sector households borrow from banks to finance their purchases of houses and they lend to banks to save for retirement banks pool households savings and they purchase interest bearing government debt and non interest bearing reserves we use this structure to answer two sets of questions one normative in nature that evaluates the welfare costs of alternative monetary and tax policies and one positive in nature that studies the real effects of following a procyclical interest rate policy rule

some empirical evidence on the effects of shocks to monetary policy on exchange rates this paper investigates the effects of shocks to u s monetary policy on exchange rates we consider three measures of these shocks orthogonalized shocks to the federal funds rate orthogonalized shocks to the ratio of nonborrowed to total reserves and changes in the romer and romer index of monetary policy in sharp contrast to the literature we find substantial evidence of a link between monetary policy and exchange rates specifically according to our results a contractionary shock to u s monetary policy leads to i persistent significant appreciations in u s nominal and real exchange rates and ii significant persistent deviations from uncovered interest rate parity in favor of u s interest rates

money demand and seigniorage maximizing inflation conventional estimates of the seigniorage maximizing inflation rate often make use of the cagan form which implies a constant semielasticity of money demand with respect to inflation this paper shows that the elasticity of substitution in transactions between money and bonds determines how the inflation semielasticity of money demand changes as inflation rises allowing for a variable semielasticity estimates of seigniorage maximizing inflation for a panel of eleven high inflation countries are lower than those obtained by using the cagan form estimates based on the correct measure of the opportunity cost of money also differ sharply from those obtained when using conventional inflation measures copyright 1995 by ohio state university press

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

fighting inflation with high interest rates the small open economy case under flexible prices in high inflation countries policymakers often end up paying interest on part of the money supply higher interest rates on money have been used both to reduce inflation and to defend the domestic currency this paper analyzes the effectiveness of such a policy in the context of an open economy with flexible prices and exchange rates a temporary increase in the interest rate on money reduces the price level on impact but inflation follows an explosive path afterwards the domestic currency appreciates on impact but begins to depreciate immediately thereafter hence the analysis does not support the use of high interest rates in disinflationary programs copyright 1995 by ohio state university press

the speed of employer learning the employer learning literature finds support for statistical discrimination on the basis of schooling how economically relevant statistical discrimination is depends on how fast employers learn about workers productive types this article is the first to estimate the speed of employer learning employers learn quickly initial expectation errors decline by 50 within 3 years this estimate places an upper bound on the contribution of signaling this bound varies with the speed of employer learning and with discount rate for a wide range of parameter values the contribution of signaling to the gains from schooling is less than 25

interest rates and the exchange rate a non monotonic tale abstract for over 30 years the empirical international finance literature has been unable to detect a clear systematic relationship between interest rates and the nominal exchange rate we take a fresh look at the data and uncover a new stylized fact for a cross section of countries the relationship between the exchange rate and short term interest rates is non monotonic small increases in the nominal interest rate appreciate the currency whereas larger increases depreciate the currency we develop a model that explains this stylized fact based on the interaction of three effects higher interest rates increase money demand and hence appreciate the currency but also raise the fiscal deficit and depress output both of which tend to depreciate the currency we provide cross country evidence for the presence of these effects in the data

mismatch of talent evidence on match quality entry wages and job mobility we examine the impact of mismatch on entry wages separations and wage growth using unique data on worker talents we show that workers are sorted on comparative advantage across jobs within occup

learning by doing vs learning about match quality can we tell them apart understanding the accumulation of match specific capital is crucial in shedding light on the reasons for the prevalence of long term employ ment relationships and on the welfare consequences of turnover in the labor market one of the most important source of match specific capital is human capital acquired through match specific learning such learn ing can take on two distinct forms in the first case workers accumulate match specific human capital through learning by doing in the second case a worker and a firm in an employment relationship learn about the quality of the match over time thereby acquiring valuable information i construct a structural model that embeds these two learning explana tions i show that it is possible to distinguish the two explanations given turnover data on employing firms coupled with data on workers such data now exist in the form of matched employer employee data sets i use a matched french data set to estimate the structural model using the efficient method of moments a simulation based estimation method i find that while learning by doing could be present in the first few months of an employment relationship learning about match quality dominates at tenures above half a year this finding has important consequences for economists understanding of the sources of match specific capital and for the desirability of policies that alter the incentives for turnover for workers of different tenure

the right man for the job this paper describes a search model with a continuum of worker and job types free entry and transferable utility we apply a second order taylor expansion to characterize the equilibrium derive the cost of search and show that it is decreasing in the substitutability of worker types this cost of search is then decomposed into three components unemployment vacancy costs and mismatch our contact technology rules out congestion effects between different worker types and therefore exhibits increasing returns to scale one third of those increasing returns in contacts are shown to be absorbed by firms and workers being more choosy the resulting equilibrium is not efficient unemployment benefits can reduce the loss by serving as a search subsidy numerical simulations of the model show that our taylor expansions are quite accurate 2004 the review of economics studies limited

assortative matching with explicit search costs in this paper i analyze a decentralized search and matching economy with transferable utility composed of heterogeneous agents i explore whether becker s assortative matching result generalizes to an economy where agents engage in costly search in an economy with explicit additive search costs complementarities in joint production supermodularity of the joint production function lead to assortative matching this is in contrast to previous literature which had shown that in a search economy with discounting assortative matching may fail even when the joint production function is supermodular

the modern history of exchange rate arrangements a reinterpretation we develop a novel system of reclassifying historical exchange rate regimes one key difference between our study and previous classifications is that we employ monthly data on market determined parallel exchange rates going back to 1946 for 153 countries our approach differs from the imf official classification which we show to be only a little better than random it also differs radically from all previous attempts at historical reclassification our classification points to a rethinking of economic performance under alternative exchange rate regimes indeed the breakup of bretton woods had less impact on exchange rate regimes than is popularly believed

currency fluctuations in the post bretton woods era the international monetary landscape that has emerged since the felling of bretton woods is characterized by a hybrid exchange rate system that lies somewhere between the textbook polar cases of a gold standard and a pure float this system has relatively flexible exchange rates between major countries active central bank intervention in the market for the major currencies and predominantly fixed exchange rates relative to the dollar or to some basket of currencies for less developed countries and newly industrializing nations the majority of research on currency markets since the early 1970s has focused on the characteristics of flexible exchange rates under this hybrid regime my thesis is that this research has been unsuccessful the proportion of monthly or quarterly exchange rate changes that current models can explain is essentially zero even after the fact forecasts that use actual values instead of forecasted values of the explanatory variables cannot explain major currency movements over the post bretton woods era this result is quite surprising since exchange rate changes would be entirely unpredictable only in very special cases of the theoretical models discussed as the discussion below will argue it is not a general implication of market efficiency that exchange rates follow a random walk process 1

the bayesian foundations of solution concepts of games abstract we transform a noncooperative game into a bayesian decision problem for each player where the uncertainty faced by a player is the strategy choices of the other players the priors of other players on the choice of other players the priors over priors and so on we provide a complete characterization between the extent of knowledge about the rationality of players and their ability to successively eliminate strategies which are not best responses this paper therefore provides the informational foundations of iteratively undominated strategies and rationalizable strategic behavior b d bernheim econometrica 52 1984 1007 1028 d pearce econometrica 52 1984 1029 1050 sufficient conditions are also found for nash equilibrium behavior and a result akin to r j aumann econometrica 55 1987 1 18 on correlated equilibria is derived with different hypotheses

correlated equilibrium as an expression of bayesian rationality if it is common knowledge that the players in a game are bayesian utility maximizers who treat uncertainty about other players actions like any other uncertainty then the outcome is necessarily a correlated equilibrium random strategies appear as an expression of each player s uncertainty about what the others will do not as the result of willful randomization use is made of the common prior assumption according to which differences in probability assessments by different individuals are due to the different information that they have where information may be interpreted broadly to include experience upbringing and genetic makeup copyright 1987 by the econometric society

unemployment vs mismatch of talents reconsidering unemployment benefits we develop an equilibrium search matching model with risk neutral agents and two sided ex ante heterogeneity unemployment insurance has the standard effect of reducing employment but also helps workers to get a suitable job we show through calibrations how the mere difference on unemployment insurance when countries experience a common skilled biased technological shock may result in differences in unemployment productivity growth and wage inequality these results are consistent with the contrasting performance of the labour market in europe and the united states in the last twenty five years the model is used to address some political economy issues

job duration seniority and earnings an important stylized fact about labor markets is that workers with longer seniority with their current employer have higher earnings than other workers with the same total labor market experience this study shows that workers in longer jobs earn more throughout than workers in a series of shorter jobs and that the measured positive cross sectional return seniority is largely a statistical artifact due to the correlation of seniority with an omitted variable representing the quality of the worker the job or the worker employer match the implication is tha t earnings do not in fact rise very much with seniority copyright 1987 by american economic association

wages and job mobility of young workers this paper presents a discrete time version of jovanovic s model of worker firm matching descriptive evidence is presented that supports the notion that unobserved worker firm heterogeneity is an important component in the intertemporal structure of wages for young workers a structural econometric model of wage dynamics under worker firm sorting is developed and estimated finally a formal test of the matching model is carried out and the matching structure on intertemporal covariances of wages is not rejected my results indicate the necessity of jointly considering processes of turnover and wage growth when analyzing the labor market experiences of young workers

taylor rules and the deutschmark dollar real exchange rate we explore the link between an interest rate rule for monetary policy and the behavior of the real exchange rate the interest rate rule in conjunction with some standard assumptions implies that the deviation of the real exchange rate from its steady state depends on the present value of a weighted sum of inflation and output gap differentials the weights are functions of the parameters of the interest rate rule an initial look at german data yields some support for the model

a new database on the structure and development of the financial sector this article introduces a new database of indicators of financial structure and financial development across countries and over time the database is unique in that it combines a wide variety of indicators that measure the size activity and efficiency of financial intermediaries and markets it improves on previous efforts by presenting data on the public share of commercial banks introducing indicators of the size and activity of nonbank financial institutions and constructing measures of the size of bond and primary equity markets this article introduces a new database the first to provide comprehensive measures of the development structure and performance of the financial sector this database is the first to define and construct indicators of the size and activity of nonbank financial intermediaries such as insurance companies pension funds and non deposit money banks it is also the first to include indicators of the size of primary equity markets and primary and secondary bond markets in constructing the database authors carefully deflate measures and match stock and flow variables

banks and macroeconomic disturbances under predetermined exchange rates abstract as the recent mexican crisis vividly illustrates latin american countries often go through boom bust cycles caused by both domestic policies and external shocks such cycles are typically magnified by weak banking systems which intermediate large capital inflows this paper develops a simple optimizing model to analyze how the banking sector affects the propagation of shocks in particular we show how the world business cycle and shocks to the banking system affect output and employment through fluctuations in bank credit we also analyze the countercyclical use of reserve requirements econometric evidence for chile and mexico supports the main predictions of the model

undominated equilibria in games with strategic complementarities abstract we analyze the problem of existence of undominated pure strategy nash equilibria in games with strategic complementarities a nash equilibrium is undominated if no player s equilibrium strategy is weakly dominated by another pure strategy we show the existence of the least and the greatest undominated equilibrium the equilibrium strategies of these extremal equilibria are undominated against mixed strategies as well and have nice comparative statics properties journal of economic literature classification number c72

games of perfect information predatory pricing and the chain store paradox the thesis of this paper is that finite noncooperative games possessing both complete and perfect information ought to be treated like one player decision problems that is players ought to assign at every move subjective probabilities to every subsequent choice in the game and ought to make decisions via backward induction this view is in contrast with the gametheoretic approach of nash equilibrium after expanding on this view for games in the abstract in sections 2 and 3 attention is turned in section 4 to an example due to reinhard selten called the chain store paradox which possesses the flavor of a situation involving a predatory pricing monopolist it is argued that for the chain store game the decision analytic approach leads under certain assumptions to more realistic outcomes than the standard nash equilibrium approach

on the job search mismatch and efficiency this paper characterizes the equilibrium for a large class of search models with two sided heterogeneity and on the job search besides the well known congestion externalities we show that on the job search in combination with monopsonistic wage setting without commitment creates a business stealing externality in the absence of congestion effects this leads to excessive vacancy creation under wage setting with commitment this externality is absent because when posting a wage firms take into account the expected productivity of future workers in their current jobs if firms are able to make and respond to counteroffers then they will not have to pay no quit premia and this also leads to excessive vacancy creation

rational behavior with payoff uncertainty abstract the iterated deletion of weakly dominated strategies has been advanced as a necessary requirement for rational play however this requirement relies on the assumption that the players have no doubts about their opponents payoffs we show that once such doubts are introduced all that can be justified by an appeal to rationality is one round of deletion of weakly dominated strategies followed by iterated deletion of strategies that are strongly dominated this extends the fudenberg kreps and levine j econ theory 12 1988 354 380 study of the robustness of nash equilibrium refinements to the robustness of solution concepts based only on rationality our results also clarify the relationship between various notions of what it means for payoff uncertainty to be small

life cycle variations in the association between current and lifetime income replication and extension for sweden we apply haider and solon s generalized errors in variables model to swedish income tax data to produce estimates of the association between current and lifetime income our estimates demonstrate strong life cycle patterns this implies that the widespread use of current income as a proxy for lifetime income leads to inconsistent parameter estimates i e life cycle bias even when the proxy is used as the dependent variable estimates for comparable cohorts of swedish and american men demonstrate surprising similarities there are however significant gender and cohort differences in this association that lead to statistically significant and quantitatively meaningful differences in life cycle biases

does inflation increase after a monetary policy tightening answers based on an estimated dsge model abstract this paper estimates the importance of the cost channel of monetary policy in a new keynesian model of the business cycle a model with nominal and real rigidities is extended by assuming that a fraction of firms need to borrow money to pay their wage bill hence a monetary policy tightening increases effective unit labor costs of production and might imply an increase in inflation the paper examines the conditions under which the model can generate a positive response of inflation to a monetary contraction and estimates the model s parameters using bayesian methods the paper shows that the estimated demand side effects of monetary policy dominate the estimated supply side effect even if restrictions are imposed that make occurrence of a positive inflation response to a monetary contraction more likely

identifying sorting in theory assortative matching between workers and rms provides evidence of the complementarities or substitutes in production the presence of complementarities is important for policies that aim to achieve the optimal allocation of resources for example unemployment insurance we argue that using wage data alone it is virtually impossible to identify whether assortative matching is positive or negative even though we cannot identify the sign of the sorting we can identify the strength i e the magnitude of the cross partial and the associated welfare loss we show rst that the wage for a given worker is non monotonic in the type of his employer this is due to the fact that in a sorting model wages reect the opportunity cost of mismatch we show analytically that this non monotonicity prevents standard rm xed eects to correlate with the true type of the rm we then propose an alternative procedure that measures the strength of sorting in the presence of search frictions knowing the strength of sorting facilitates the measurement of the output loss due to mismatch

do high interest rates defend currencies during speculative attacks abstract do high interest rates defend currencies during speculative attacks or do they have the perverse effect of increasing the probability of a devaluation of the currency under attack drawing on evidence from a large sample of speculative attacks in developed and developing economies this paper argues that the answer to both questions is no in particular this paper documents a striking lack of any systematic association whatsoever between interest rates and the outcome of speculative attacks the lack of clear empirical evidence on the effects of high interest rates during speculative attacks mirrors the theoretical ambiguities on this issue

rationalizability learning and equilibrium in games with strategic complementarities we study a rich class of noncooperative games that includes models of oligopoly competition macroeconomic coordination failures arms races bank runs technology adoption and diffusion r d competition pretrial bargaining coordination in teams and many others for all these games the sets of pure strategy nash equilibria correlated equilibria and rationalizable strategies have identical bounds also for a class of models of dynamic adaptive choice behavior that encompasses both best response dynamics and bayesian learning the players choices lie eventually within the same bounds these bounds are shown to vary monotonically with certain exogenous parameters we study the class of noncooperative supermodular games introduced by topkis 1979 and further analyzed by vives 1985 1989 who also pointed out the importance of these games in industrial economics supermodular games are games in which each player s strategy set is partially ordered the marginal returns to increasing one s strategy rise with increases in the competitors strategies so that the game exhibits strategic complementarity 2 and if a player s strategies are multidimensional marginal returns to any one com ponent of the player s strategy rise with increases in the other components this class turns out to encompass many of the most important economic applications of noncooperative game theory in macroeconomics diamond s 1982 search model and bryant s 1983 1984 rational expectations models can be represented as supermodular games in each of these models more activity by some members of the economy raises the returns to increased levels of activity by others in oligopoly theory some models of bertrand oligopoly with differentiated products qualify as supermodu lar games in these games when a firm s competitors raise their prices the marginal profitability of the firm s own price increase rises a similar structure is present in games of new technology adoption such as those of dybvig and spatt 1983 farrell and saloner 1986 and katz and shapiro 1986 when more users hook into a communication system or more manufacturers adopt an interface standard the marginal return to others of doing the same often rises similarly in some specifications of the bank runs model introduced by diamond and dybvig 1983 when more depositors withdraw their funds from a bank it is more worthwhile for other depositors to do the same in the warrant exercise

reserve requirements and the inflation tax the inflation tax on currency and required bank reserves is modeled in a general equilibrium setting by specifying a transactions technology in which currency and demand deposits allow agents to economize on time spent transacting in the goods market revenue maximizing conditions for the nominal interest rate and reserve ratio are analyzed for any given revenue requirement less than the revenue maximizing level minimization of the welfare costs of inflationary finance results in the choice of a combination of the interest rate and reserve ratio that lies on a set of tangency points formed by iso revenue and iso welfare curves copyright 1989 by ohio state university press

out of sample exchange rate predictability with taylor rule fundamentals abstract an extensive literature that studied the performance of empirical exchange rate models following meese and rogoff s meese r a rogoff k 1983a empirical exchange rate models of the seventies do they fit out of sample journal of international economics 14 3 24 seminal paper has not convincingly found evidence of out of sample exchange rate predictability this paper extends the conventional set of models of exchange rate determination by investigating predictability of models that incorporate taylor rule fundamentals we find evidence of short term predictability for 11 out of 12 currencies vis a vis the u s dollar over the post bretton woods float with the strongest evidence coming from specifications that incorporate heterogeneous coefficients and interest rate smoothing the evidence of predictability is much stronger with taylor rule models than with conventional interest rate purchasing power parity or monetary models

returns to job satisfaction in the presence of horizontal mismatch in this paper we study the relationship among horizontal mismatch job satisfaction and wages using data from the 2013 scientists and engineers statistical data system sestat estimates from 2sl