target zones and interest rate variability abstract for narrow exchange rate bands and for reasonable parameter values the interest rate differential s asymptotic unconditional variability is increasing in the width of the exchange rate band whereas for wide exchange rate bands it is slowly decreasing in the exchange rate band the interest rate differential s instantaneous conditional variability is decreasing in the width of the exchange rate band a narrow target zone differs from a completely fixed exchange rate regime in that the interest rate differential s instantaneous standard deviation is high and even increases when the zone narrows

the forecasting ability of correlations implied in foreign exchange options abstract this paper evaluates the forecasting accuracy of correlations derived from implied volatilities in dollar mark dollar yen and mark yen options from january 1989 to may 1995 as a forecast of realized correlation between the dollar mark and dollar yen implied correlation is compared against three alternative forecasts based on time series data historical correlation riskmetrics exponentially weighted moving average correlation and correlation estimated using a bivariate garch 1 1 model at the 1 month and 3 month forecast horizons we find that implied correlation outperforms often significantly these alternative forecasts in combinations implied correlation always incrementally improves the performance of other forecasts but not the converse in certain cases historically based forecasts contribute no incremental information to implied forecasts the superiority of the implied correlation forecast holds even when forecast errors are weighted by realized variances reflecting correlation s contribution to the dollar variance of a multicurrency portfolio

a simplified jump process for common stock returns the specification of a statistical distribution which accurately models the behavior of stock returns continues to be a salient issue in financial economics with the introduction of arithmetic and geometric brownian motion models much attention has recently focused on a poisson mixture of distributions as an appropriate specification of stock returns for example see 12 3 8 10 5 and 1 consistent with empirical evidence these models yield leptokurtic security return distributions and furthermore the specification has much economic intuition in particular one may always decompose the total change in stock price into normal and abnormal components the normal change may be due to variation in capitalization rates a temporary imbalance between supply and demand or the receipt of any other information which causes marginal price changes this component is modelled as a lognormal diffusion process the abnormal change is due to the receipt of any information which causes a more than marginal change in the price of the stock and is usually modeled as a poisson process

exchange rate target zones a survey of the literature this work selectively reviews the literature on exchange rate target zones and their theoretical and empirical methodologies and examines whether they can be used to clarify to what extent this type of exchange rate regime could contribute to greater exchange rate stability we discuss the main contributions of the first and second generations of exchange rate target zone models in an attempt to reconcile the poor empirical performance of the krugman model with the reality of exchange rate target zone regimes this line of research integrates target zones with alternative underlying economic models such as imperfect credibility intra marginal interventions and sticky price models it was thus possible to understand the correlations observed between the exchange rate its fundamentals determinants and the interest rate differential and to explain the fact that the statistical distribution of the exchange rate is hump shaped rather than u shaped this implies that the initial emphasis of target zone models on nonlinearities honeymoon effect smooth pasting and marginal interventions has vanished exchange rate target zones are better described as similar to managed floating regimes with intra marginal interventions with some marginal interventions when the exchange rate reaches the edges of the floating band

currency substitution and exchange rate volatility in the european community abstract some proponents of a european monetary union worry that capital mobility and currency substitution will result in unmanageable exchange rate volatility during the transition to monetary union in this paper we analyze stylized models of exchange rate fluctuation in response to monetary disturbances we find that if monetary policies within the community are convergent higher currency substitution either reduces or does not significantly change the volatility of exchange rates unless there are anticipations of a final realignment

realignment risk and currency option pricing in target zones abstract this paper extends the krugman target zone model by including a realignment mechanism various properties of that realignment mechanism are discussed the movement of the exchange rate is governed both by a wiener process on fundamental and by a poisson jump process with endogenous realignment size the realignment mechanism is such that except in cases where a speculative attack occurs no jump in fundamental is needed to accompany the jump in the exchange rate a risk neutral valuation of currency options is constructed some properties of option values under realignment risk are illustrated by numerical results

hysteresis bands on returns holding period and transaction costs abstract in the presence of transactions costs no matter how small arbitrage activity does not necessarily render equal all riskless rates of return when two such rates follow stochastic processes it is not optimal immediately to arbitrage out any discrepancy that arises between them the reason is that immediate arbitrage would induce a definite expenditure of transactions costs whereas without arbitrage intervention there exists some perhaps sufficient probability that these two interest rates will come back together without any costs having been incurred hence one can surmise that at equilibrium the financial market will permit the coexistence of two riskless rates that are not equal to each other for analogous reasons randomly fluctuating expected rates of return on risky assets will be allowed to differ even after correction for risk leading to important violations of the capital asset pricing model the combination of randomness in expected rates of return and proportional transactions costs is a serious blow to existing frictionless pricing models

learning about intervention target zones abstract this paper provides a framework for evaluating how market participants beliefs about foreign exchange target zones change as they learn about central bank intervention policy we generalize the standard target zone model to allow for intra marginal intervention intra marginal intervention implies that market participants beliefs about the target zone can be determined from their beliefs about the likelihood of intervention we then estimate a daily probability of intervention model for the period following the louvre accord we find that the market s views of intervention target zones would have varied quite a bit over time even over this relatively stable period

recent developments in international finance a guide to research abstract this is a critical evaluation of the state of the art in international finance several points of reference are selected the mundell fleming branson mfp paradigm the monetary model with purchasing power parity ppp as a long run anchor the representative agent approach and the natural real exchange rate natrex model their strengths and weaknesses are identified from both a theoretical and empirical point of view we conclude with a suggestion of what is a fruitful explanation of medium to longer run movements in the real exchange rate and the current account

analytical approximations in models of hysteresis decisions made under ongoing uncertainty and costly reversibility entail a range of the state variable where inaction is optimal which in turn produces hysteresis permanent effects of temporary shifts the range is usually defined by non linear equations that need numerical solutions in this paper a technique of analytical approximations is developed and applied to two models menu costs and investment the resulting explicit solutions help clarify why hysteresis is important even for small irreversibility in the menu cost model hysteresis is two orders of magnitude larger than under the akerlof yellen or mankiw assumptions when decisions that are costly to reverse are made under conditions of ongoing uncertainty the optimum policy usually entails a range of inertia the action should be taken only when the value of the underlying state variable becomes especially favourable and reversed only when it becomes especially unfavourable there is an intermediate range over which inaction is optimal this in turn gives rise to hysteresis starting from a value in the range of inertia if the state variable crosses the action trigger point and then returns to its original level the action will be taken but not reversed thus a temporary change will leave a permanent effect numerical solutions for models of irreversible investment show that the range of inaction is remarkably large even when the cost of reversal is small see brennan and schwartz 1985 constantinides 1986 and dixit 1989a b for examples of this unfortunately the equations tlhat determine the optimum policy are highly non linear they do not have analytical solutions therefore we lack a clearer and more general understanding of why hysteresis is numerically so important in this paper i derive analytical approximations for the solutions of more general problems of this kind when the costs of change are small the idea that small costs of change induce large amounts of inertia has been popularized in the model of akerlof and yellen 1985 mankiw 1985 and others in these models second order small costs of making price changes yield price stickiness in response to first order changes in the money supply this is a simple application of the envelope theorem but these models are static and their application to a dynamic reality must assume either permanent shocks or static expectations when there is ongoing uncertainty which is rationally expected by the decision maker the option value of the status quo enlarges the zone where inaction is optimal adding these features to the mankiw akerlof yellen may model i show that fourth order small costs of change generate first order inertia

option prices as predictors of equilibrium stock prices the black scholes option pricing model modified for dividend payments is used to calculate jointly implied stock prices and implied standard deviations a comparison of the implied stock prices with observed stock prices reveals that the implied prices contain information regarding equilibrium stock prices that is not fully reflected in observed stock prices the implications of this finding are discussed this study investigates the role of call option prices as predictors of the equilibrium prices of their underlying stocks using the black scholes 3 bs model previous tests of the bs model have shown that the formula is highly successful in explaining the observed market prices of options see black and scholes 2 galai 8 chiras and manaster 6 and macbeth and merville 12 according to the model the option price is a function of the current value of the underlying stock the instantaneous variance of the stock s rate of return the time to maturity of the option the risk free rate of interest and the exercise price of the option 1 given an observed option price and known values of all input parameters to the bs model except the stock price one can determine the price of the underlying stock that equates the observed option price to its calculated value it follows from the underlying logic of the model that the implied price is the value of the underlying stock for which a continuously revised option bond portfolio would be a perfect substitute for the stock hence if options are actually priced according to the model implied stock prices will be the option market s assessment of equilibrium stock values previous empirical studies have assumed that observed stock prices are the relevant stock prices for option valuation however just as stock prices may differ in the short run from one exchange to another i e nyse midwest

target zones and exchange rate dynamics this paper develops a simple model of exchange rate behavior under a target zone regime it shows that the expectation that monetary policy will be adjusted to limit exchange rate variation affects exchange rate behavior even when the exchange rate lies inside the zone and is thus not being defended actively somewhat surprisingly the analysis of target zones turns out to have a strong formal similarity to problems in option pricing and investment under uncertainty

why exchange rate bands monetary independence in spite of fixed exchange rates abstract the paper argues that the reason real world fixed exchange rate regimes usually have finite bands instead of completely fixed exchange rates between realignments is that exchange rate bands counter to the textbook result give central banks some monetary independence even with free international capital mobility the nature and amount of monetary independence is specified informally and in a formal model and quantified with swedish krona data altogether the amount of monetary independence appears sizable for instance an increase in the swedish krona band from zero to about 2 percent may reduce the krona interest rate s standard deviation by about a half

target zones and exchange rates an empirical investigation this paper develops an empirical model of exchange rates in a target zone the distribution of exchange rate changes is conditioned on a latent jump variable where the probability and size of a jump vary over time as a function of financial and macroeconomic variables when there is no jump the target zone is credible and exchange rate changes are constrained to remain within the target zone band the paper revisits the empirical evidence from the european monetary system regarding the conditional distribution of exchange rate changes the credibility of the system and the size of the foreign exchange risk premia in contrast to some previous findings we conclude that the french franc deutschmark rate exhibits considerable nonlinearities realignments are somewhat predictable and the credibility of the system did not increase substantially after 1987 moreover our model implies that the foreign exchange risk premium becomes large during speculative crises

the statistical properties of daily foreign exchange rates 1974 1983 abstract this paper examines the statistical properties of daily rates of change of five foreign currencies from 1974 to 1983 the main purpose is to discriminate between two competing explanations for the observed heavy tails of the distribution that the data are independently drawn from a heavy tail distribution which remains fixed over time and that the data come from distributions which vary over time evidence point to the rejection of the first hypothesis further investigations show that the rejection can be attributed to changing means and variances in the data which can be described by a simple statistical model

how long do unilateral target zones last abstract we examine the expected survival time of a unilateral exchange rate target zone when constraints on monetary policy prevent the central bank from exclusively focusing on defending the target zone generally the width of the target zone has a negligible effect on the expected survival time and the dominant determinants are reserve levels and the degree of real and monetary divergence between the country in question and the rest of the world for seemingly realistic parameters the expected survival time is fairly long a few decades rather than a few years

using option prices to estimate realignment probabilities in the european monetary system the case of sterling mark abstract this paper describes a procedure for estimating the market s perceived probability distribution of future exchange rates from the prices of risk reversals strangles and other currency options and uses the procedure to estimate the risk neutral ex ante probability of a realignment of the pound sterling the procedure for estimating the realignment probabilities relies on the jump diffusion model of exchange rate behavior and the resulting option pricing formula by fitting this model to market option price data i retrieve the unobserved parameters of the jump diffusion process i then use these parameter estimates to estimate the ex ante probability distribution of exchange rates and thus the realignment probabilities

the handbook of international macroeconomics preface 1 introduction rick van der ploeg amsterdam 2 quantity constrained models of open economies neil rankin warwick 3 imperfect competition and open economy macroeconomics huw d dixon york 4 relative price movements in dynamic general equilibrium models of international trade david backus nyu patrick kehoe pennsylvania and finn kydland carnegie mellon 5 international fiscal policy coordination and competition assaf razin and efraim sadka tel aviv 6 capital taxation in the world economy a lans bovenberg tilburg 7 history of the international monetary system implications for research in international macroeconomics and finance barry eichengreen berkeley 8 on inflation unemployment and the optimal exchange rate regime george alogoskoufis athens 9 macroeconomic policy speculative attacks and balance of payments crisis pierre richard agenor and robert p flood imf 10 continuous time models of exchange rates and intervention giuseppe bertola princeton 11 stylized facts of nominal exchange rate returns casper g de vries leuven 12 partial versus general equilibrium models of international capital market equilibrium 13 sovereign debt kenneth kletzer santa cruz 14 growth and external debt daniel cohen cepremap 15 growth and deficits in an interdependent world index

on jumps in common stock prices and their impact on call option pricing the black scholes call option pricing model exhibits systematic empirical biases the merton call option pricing model which explicitly admits jumps in the underlying security return process may potentially eliminate these biases we provide statistical evidence consistent with the existence of lognormally distributed jumps in a majority of the daily returns of a sample of nyse listed common stocks however we find no operationally significant differences between the black scholes and merton model prices of the call options written on the sampled common stocks

assessing target zone credibility mean reversion and devaluation expectations in the erm 1979 1992 abstract the paper presents estimates of devaluation expectations for six erm currencies relative to the deutsche mark for the period march 1979 april 1992 both the simplest test and the drift adjustment method are used the simplest test adjusts interest rate differentials for the maximum and minimum expected rate of depreciation within the exchange rate band the drift adjustment method adjusts interest rate differentials by the estimated expected rate of depreciation within the band the latter method gives more precise estimates especially for short horizons and allows statistical inference and hypothesis testing expected rates of devaluation have generally fallen during the period still some devaluation expectations relative to the deutsche mark remain in 1992 except for the belgian luxembourg franc and the netherlands guilder expected rates of devaluation have fluctuated more than interest rate differentials

arbitrage based tests of target zone credibility evidence from erm cross rate options this paper introduces two arbitrage based tests of target zone credibility using a new data source exchange rate mechanism cross rate options using daily option prices from september 1991 to august 1994 the authors assess the credibility of the pound mark and mark lira target zones that collapsed in september 1992 and the ongoing mark french franc target zone these tests are based on restrictions that must apply to all option prices within a credible target zone and are free from specification error and estimation error the authors also identify a minimum intensity of realignment an expression indicating the probability weighted average realignment size copyright 1996 by american economic association

an arbitrage free trilateral target zone model abstract this paper proposes an arbitrage free trilateral model of a credible target zone regime with bands on each bilateral exchange rate the no arbitrage condition reduces the system to only two dimensions any two rates must obey their own boundaries but in addition the free rein for movements is restricted by the band of the redundant rate therefore target zone models defined in bilateral settings do not apply to general systems with a cobweb of bilateral bands such as the european monetary system since the model has no known analytical solution it is estimated by the method of simulated moments

optimal target zones how an exchange rate mechanism can improve upon discretion abstract using krugman s 1991 target zone model we find an explicit subgame perfect solution for a central bank wishing to stabilise the exchange rate given proportional costs of intervention we demonstrate however that precommitment to narrower bands would yield a welfare gain which provides a theoretical rationale for an exchange rate mechanism erm numerical simulations suggest that the optimal currency band with precommitment via an erm is only half as wide as that under discretion and that the welfare benefits are sufficient to sustain the system

the statistical distribution of exchange rates empirical evidence and economic implications the abundant evidence that changes in exchange rates have distributions with fatter tails than the normal distribution has led researchers to consider non normal distributions including the student the stable paretian and mixtures of distributions this paper compares the empirical fits of three non normal candidates and the normal distribution for daily changes in the logarithms of exchange rates using maximum likelihood estimation of the parameters and chi square goodness of fit tests the student and mixture of two normals provide the best fits but there is evidence that the distribution parameters may vary over time

commodity trade and the carry trade a tale of two countries persistent interest rate differentials account for much of the currency carry trade profitability commodity currencies offer high interest rates on average while countries that export finished goods tend to have low interest rates we develop a general equilibrium model of international trade and currency pricing where countries have an advantage in producing either basic inputs or final goods in the model domestic production insulates commodity producing countries from global productivity shocks forcing final good producers to absorb them commodity currency exchange rates and risk premia increase with productivity differentials and trade frictions these predictions are strongly supported in the data this article is protected by copyright all rights reserved

target zones and the distribution of exchange rates abstract we develop a parsimonious parameterization of exchange rate density function under target zones that enables us to estimate the approximate shapes of density curves from the exchange rate data we find that the distributions of exchange rates can take several different shapes which may correspond to possibly widely different monetary and exchange rate intervention policies including the marginal and intramarginal intervention policies discussed in previous theoretical models

interest rate differentials and exchange rate policies in austria the netherlands and belgium in this paper the small but persistent interest rate differentials via a vis germany which have existed in austria the netherlands and belgium are analysed these interest differentials may be thought of to consist of three parts expected exchange rate movements within the band expected changes of the central rates and a risk premium following a similar test as proposed by svensson we examine the credibility of the exchange rate policy in these countries according to this test the belgian exchange rate policy clearly lacks credibility for most of the period under consideration there are however serious problems applying this test to belgium due to the dual exchange rate system for austria and the netherlands we calculate interest differentials which are adjusted for expected exchange rate movements within the band it appears that the differences between the adjusted and the unadjusted interest differentials can be substantial the granger causal relationship between fundamentals like the rate of inflation the government budget deficit and the current account is also quite different for the adjusted and the unadjusted interest differential where the fundamentals have the highest explanatory power for the latter measure

an interpretation of recent research on exchange rate target zones how do exchange rate bands work compared to completely fixed rates between realignments or more precisely what are the dynamics of exchange rates interest rates and central bank interventions within exchange rate bands does the difference between bands and completely fixed exchange rates matter and if so which of the two arrangements is best or more precisely what are the tradeoffs that determine the optimal bandwidth this article will present an interpretation of some selected recent theoretical and empirical research on exchange rate target zones with emphasis on main ideas and results and without technical detail

the scope for monetary independence in exchange rate target zones broad and narrow abstract placing limits on the movement of economic fundamentals in order to maintain an exchange rate within a target zone also puts a target zone around interest rate differentials the bandwidth of exchange rate and interest rate differentials target zones will be different except at one point it is suggested that this point gives a useful partitioning of target zones into broad and narrow categories for realistic parameter values this occurs at an exchange rate target zone of plus or minus 3 2

a new breed of exchange rate bands chile israel and mexico following inflation stabilization programmes where a fixed exchange rate is used as an anchor a number of countries have gradually shifted towards a regime of increased flexibility in particular chile israel and mexico have adopted for a few years a regime of crawling exchange rate bands this article documents and analyzes their unique experience of immediate concern is the question whether the shift from fixed to crawling bands is perceived as the signal of a tilt towards policy relaxation on the contrary it could be seen as a way of restoring external competitiveness after a period of real appreciation the evidence collected in this article supports the latter view as a way of moving towards a sustainable equilibrium the shift to crawling bands is found to have a stabilizing influence on financial markets on inflation expectations and on the passthrough from exchange rates to prices

cross country differences in monetary policy execution and money market rates volatility abstract volatility patterns in overnight interest rates display differences across industrial countries that existing models designed to replicate the features of individual countries markets cannot account for this paper presents an equilibrium model of the overnight interbank market that matches cross country differences in patterns in interest volatility by incorporating differences in how central banks manage liquidity in response to shocks our model is consistent with central banks practice of rationing access to marginal facilities when the objective of stabilizing short term interest rates conflicts with another high frequency objective such as an exchange rate target

testing the basic target zone model on swedish data 1982 1990 the swedish exchange rate band is studied using daily data on exchange rates and interest rate differentials for the 1980s applying a number of different statistical and econometric techniques it is found that the first generation of target zone models cannot provide an adequate explanation of swedish data the main reasons are probably intra marginal interventions by the swedish central bank and time varying devaluation expectations

the crash of ʼ87 was it expected the evidence from options markets transactions prices of s p 500 futures options over 1985 1987 are examined for evidence of expectations prior to october 1987 of an impending stock market crash first it is shown that out of the money puts became unusually expensive during the year preceding the crash second a model is derived for pricing american options on jump diffusion processes with systematic jump risk the jump diffusion parameters implicit in options prices indicate that a crash was expected and that implicit distributions were negatively skewed during october 1986 to august 1987 both approaches indicate no strong crash fears during the 2 months immediately preceding the crash attempts to explain what caused the stock market crashes around the world in october 1987 have suffered from the paucity of major economic developments occurring around that time that could have triggered the crashes shifting expectations regarding monetary policy foreign investors fears of a dollar decline increasing riskiness of assets none of these appeared major enough if present at all to explain the magnitude of the crashes and although portfolio insurance strategies could conceivably magnify the effects of a jump in fundamentals the initiating jump in fundamentals appears to be lacking

the linkage between speculative attack and target zone models of exchange rates in this paper we generalize the target zone exchange rate as model formalized by krugman 1988b to include finite sized interventions in defense of the zone the main contributions of these pages consist of linking the recent developments in the theory of target zones to the mirror image theory of speculative attacks on asset price fixing regimes and in using aspects of that linkage to give an intuitive interpretation to the smooth pasting condition usually invoked as a terminal condition this abstract was borrowed from another version of this item

imperfect credibility and risk premia in the european monetary system the paper deals with the estiamation of models for the expected rate of depreciation within the currency bands of the french franc and the italian lira against the deutshmark both unconditional and conditional upon no realignment as well as the estimastion of models for risk premia using these estimates estimates are constructed for the expected rate of depreciation the expected rate of realignment and the expected rate of devaluation of these exchange rates during their ems period by appropriate adjustment of interest rate differentials it is found that these adjustments are of non trivial magnitude

a univariate analysis of ems exchange rates using a target zone model summary the models in the literature on exchange rate target zones imply a non linear time series model for the exchange rate we show how the parameters of such models can be estimated and develop maximum likelihood and method of simulated moments estimators for the target zone model of krugman 1991 the maximum likelihood estimator is based on a computationally attractive approximation to the exact predictive density of the continuous time model monte carlo experiments are used to assess the properties of this estimator in the empirical part we estimate the model with data on recent ems exchange rates we find that the krugman 1991 target zone model is not able to explain the full observed kurtosis and conditional heteroscedasticity of the exchange rate returns

the term structure of interest rates in a sticky price target zone model abstract the term structure of interest rates in a sticky price target zone model with perfectly credible marginal central bank intervention is identified by means of an arbitage free valuation we find that an explicit credible target zone for the exchange rate is associated with an implicit target zone for the long term interest rate where the nonlinearity of the exchange rate function translates into a corresponding stabilizing nonlinearity of the long term interest rate imposing a target zone reduces the variability of short term and long term interest rates and induces a steeper term structure relative to freely floating exchange rates

playing with the band dynamic effects of target zones in an open economy this paper applies techniques of regulated brownian motion to a model of a small open economy to investigate how bands on fundamental driving variables affect the realization of the nominal exchange rate the real exchange rate prices and output the author shows that these bands mitigate the relationship between exogenous fundamentals and endogenous variables through their effects on expectations he also considers the effects of changing the width of the band and finds greater stabilization of endogenous variables with more narrow bands on exogenous fundamentals copyright 1990 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

mixed diffusion jump process modeling of exchange rate movements this study demonstrates that the mixed diffusion jump process is superior to the stable laws or a mixture of normals as a model of exchange rate changes for the british pound french franc and the we st german mark relative to the united states dollar the parameter value s for the mixed diffusion jump process are dependent on the monetary policy regime in force in the united states with the estimates for the franc and mark being intertemporally similar but different from the pound copyright 1988 by mit press

stochastic trends and jumps in ems exchange rates abstract in this paper we study the statistical properties of ems exchange rate returns our findings show that jumps time varying parameters and conditional leptokurtosis are pertinent features in the empirical distributions of ems exchange rate returns allowance for fat tails however tends to reduce the measured frequency of jumps in the distributions to more realistic proportions most successful in capturing the relevant features of ems exchange rate returns is a combined jump garch model with conditionally t distributed innovations jel f31

on jump processes in the foreign exchange and stock markets exchange rates exhibit systematic discontinuities even after allowingfor conditional heteroskedasticity in the diffusion process the results are much more significant in theforeign exchange market than in the stock market which suggests differences in the structure of these markets finally this jump component is shown to explain some of the empirically observed mispricings in the currency options market the objective of this article is to analyze and compare the empirical distribution of returns in the stock market and in the foreign exchange market there are a number of reasons why a better understanding of the stochastic processes driving prices in these markets would be useful many financial models rely heavily on the assumption of a particular stochastic process while relatively little attention is paid to the empirical fit of the postulated distribution as a result models like option pricing models are applied indiscriminately to various markets such as the stock market and the foreign exchange market when the underlying processes may be fundamentally different the foreign exchange market for instance is characterized by active exchange rate man

a jump diffusion model for the european monetary system abstract we propose a general continuous time bivariate jump diffusion representation for the exchange rates of european currencies our model captures key features of the exchange rate mechanism fluctuation within bilateral limits is modeled by appropriate diffusion dynamics while discontinuous variation in the level of the fluctuation band is posited to have a jump structure under specific assumptions the probability distribution of the exchange rate process is derived analytically we also perform an empirical investigation of these exchange rates comparing the fit of alternative models we find some evidence of mean reversion inside the bands for these exchange rates jel f33 c51

monetary and real shocks and the optimal target zone abstract an exchange rate target zone is analysed in a model where the economy is disturbed by shocks to money demand and goods demand the stabilising properties of a target zone are compared to those of fixed and flexible exchange rate regimes it is found that a target zone offers a compromise between these two extremes it is also shown that when there are shocks to both money and goods demand a target zone is better than either a fixed rate or a floating rate in the sense that it minimises the variance of output and prices

exchange rate dynamics in anticipation of time contingent regime switching modelling the effects of a possible delay abstract the procedure of fixing a currently floating exchange rate at a given and publicly announced future date has a broad range of applications based on a continuous time monetary exchange rate model with flexible prices this paper analyzes exchange rate dynamics during the transition from floating to fixed rates in a situation in which market participants are uncertain about adherence to the fixing date and in which they take account of a possible delay in the regime switch the closed form solutions derived here allow us to quantify announcement effects as well as effects on the exchange rate variance caused by news that significantly changes the market s assessment of uncertainty

exchange rates under ems target zones an econometric investigation this study tests krugman s model on exchange rate target zones using four old ems exchange rates those of the currencies of belgium france italy and the netherlands against the deutsche mark vast theoretical literature is available but there are very few empirical studies testing the main results of krugman s model namely the honeymoon effect smooth pasting and the overall s curved relationship between fundamental and exchange rate the present study supports the honeymoon effect but does not find any evidence in support of smooth pasting or of an s curved relationship between the exchange rate and fundamentals for the belgian franc french franc and italian lira against the deutsche mark the dutch guilder very closely follows movements in the german mark throughout the period 1981 90 end of month exchange rates and euro currency interest rates data are used

sterling s erm credibility abstract this paper examines the recent credibility of the currencies participating in the erm since 1987 focusing on sterling in 1992 it shows that there is little market evidence that sterling s credibility was in serious doubt until mid september 1992

monetary contracting between central banks and the design of sustainable exchange rate zones abstract an exchange rate system is a contract which commits central banks to intervene in the foreign exchange market the design features of the system include the rules of intervention the limits placed on exchange rates and the crisis scenario describing possible transitions to new regimes this paper considers the various trade offs one faces in designing an exchange rate system one of these pertains to the amount of reserves which the central banks must have on hand in order to forestall a speculative attack and make the system sustainable the amount of reserves needed depends crucially on the assumed crisis scenario

currency option pricing with mean reversion and uncovered interest parity a revision of the garman kohlhagen model abstract we consider a model for the pricing of currency options where the logarithm of the exchange rate exhibits mean reversion i e follows the omstein uhlenbeck process we mention reasons why exchange rates could exhibit mean reversion the domestic and foreign short interest rates are related to the logarithm of the exchange rate through uncovered interest parity under these assumptions we derive formulas for the value of a european currency option from the point of view of both domestic and foreign investors we also derive formulas for options on forward and futures contracts we compare option values computed by means of the garman kohlhagen model with corresponding results from our model it appears that our model cannot explain all instances of mispricing of currency options by the garman kohlhagen model which have been reported by previous authors the main virtue of our paper however is that we derive a simple model which incorporates clear theoretical relationship between the exchange rate and the domestic and foreign interest rates

estimating credibility in colombia s exchange rate target zone abstract this paper analyzes credibility in the colombian exchange rate target zone a model of imperfect credibility in the spirit of bertola and svensson bertola g svensson l 1993 stochastic devaluation risk and the empirical fit of target zone models review of economic studies 60 689 712 is derived and estimated using colombian data the main feature of the model is that central parity depreciation expectations are endogenous with respect to the position of the exchange rate inside the target zone the krugman krugman p 1991 target zones and exchange rate dynamics quarterly journal of economics 56 3 669 682 perfectly credible setup is a particular case of this general model a key implication of the model is that depreciation expectations rise rather than fall as the exchange rate approaches the upper band using the method of simulated moments msm to estimate the structural parameters underlying the model i find evidence suggesting that colombia s exchange rate target zone is properly described by a model of this nature

modeling heteroscedasticity in daily foreign exchange rates this article estimates autoregressive conditionally heteroscedastic arch and generalized arch garch models for five foreign currencies using 10 years of daily data a variety of arch and garch specifications a number of nonnormal error densities and a comprehensive set of diagnostic checks it finds that arch and garch models can usually remove all heteroscedasticity in price changes in all five currencies goodness of fit diagnostics indicate that exponential garch with certain nonnormal distributions fits the canadian dollar extremely well and the swiss franc and the deutsche mark reasonably well only one nonnormal distribution fits the japanese yen reasonably well none fit the british pound

stochastic devaluation risk and the empirical fit of target zone models in the model of this paper an exchange rate fluctuates between given boundaries for random lengths of time and jumps discretely when devaluation occur we provide explicit solutions for the stochastic processes followed by the exchange rate and by the expected rate of depreciation when the likelihood and the size of devaluations vary stochastically over time the model produces realistic patterns of covariation between exchange rates and interest rate differentials and provides interesting interpretations of available empirical evidence we also specify how to infer devaluation risk from target zone data

implied exchange rate distributions evidence from otc option markets abstract this paper uses a rich new dataset of option prices on the dollar mark dollar yen and key ems cross rates to extract the entire risk neutral probability density function pdf over horizons of 1 and 3 months we compare three alternative smoothing methods cubic splines an implied binomial tree trimmed and untrimmed and a mixture of lognormals for transforming option data into the pdf despite their methodological differences the three approaches lead to a similar pdf clearly distinct from the lognormal benchmark and typically characterized by skewness and leptokurtosis we then document a striking positive correlation between skewness in these pdfs and the spot rate the stronger a currency the more expectations are skewed towards a further appreciation of that currency we interpret this finding as a rejection that innovations in these exchange rates are independent of the level or characteristic of a credible target zone explicit or implicit instead this positive correlation is consistent with target zones with endogenous realignment risk we discuss two interpretations of our results on skewness when a currency is stronger the actual probability of further large appreciation is higher or because of risk such states are valued more highly

the probability distribution of foreign exchange price changes tests of candidate processes this study investigates empirically candidate processes for characterizing foreign exchange price changes measured over limited horizons extant empirical studies find distributions of exchange returns too long tailed and leptokurtic to satisfy normality four processes are investigated here because of their potential to model o bserved discontinuities in exchange rates and nonstationary sample moments as well as their economic appeal the results favor a mixed jump model for all six major trading currencies tested copyright 1988 by mit press

exchange rate target zones realignments and the interest rate differential theory and evidence abstract this paper develops a target zone model for the exchange rate where the expected realignment is an increasing function of the distance of the exchange rate from the central parity as a percentage of the width of the band in this framework the interest rate differential increases with the deviation of the exchange rate from the central parity when the exchange rate is close to the central parity and it decreases when the exchange rate is close to the edges of the band finally the paper looks at the evidence from the ems and finds partial support for the implications of the model

big effects of small interventions the informational role of intervention in exchange rate policy abstract in this paper we demonstrate how an infintesimal unsterilized foreign exchange intervention may cause a very large discrete change in the exchange rate we analyze an example in which there is a target zone policy in place but the actual width of the target zone is not known by participants in the foreign exchange market in this case intervention both affects fundamentals and conveys information about policy the exchange rate jumps in response to intervention with the size of the jump related to the uncertainty about the true band width also in this model the relationship between the exchange rate and the fundamental depends upon both the history of the path of the exchange rate and whether or not intervention has occured

nonlinear dynamics and econometrics an introduction the empirical modelling of economic time series is dominated by methods that assume linearity of the underlying dynamic economic system the so called frisch slutsky paradigm the main a priori argument in favour of linearity and the reason for its original adoption is its simplicity autoregressive models can be estimated using standard regression packages and there is now a wide range of computer software packages available to estimate models with linear moving average components the dynamics contained in estimated models can be completely characterized by their impulse response functions and directly related to linear models of the macroeconomy the dominance of the frisch slutsky paradigm is not based on any strong a priori belief that the economic system is linear indeed once curvature is introduced into utility functions and or production functions nonlinearity is pervasive in theoretical dynamic models hence the shortage of closed form solutions nor is it based on any convincing empirical evidence that actual economic time series are best described as linear stochastic processes the lq optimization approach namely linear constraints and quadratic objective functions which underlies most econometric applications either implicitly or explicitly is undoubtedly attractive on analytical and computational grounds but can be highly deficient in areas where economic behaviour is dominated by asymmetric costs of adjustments irreversibilities transaction costs or institutional and physical rigidities the challenge facing applied econometrics in dealing with these issues is truly immense reliable statistical techniques are required for detecting dynamic nonlinearities stochastic optimization models that are capable of capturing the primary sources of dynamic nonlinearities and are suitable for empirical analysis need to be developed the possible effects of temporal aggregation and aggregation across commodities and agents need to be worked out in the context of nonlinear dynamic models these are complicated issues solutions to some of which have eluded us even in the case of linear models and promise to be far more complicated when we enter the realm of nonlinear dynamic models it is therefore natural to expect that real progress in the area of nonlinear dynamic econometric models will be slow and hard to come by nevertheless the past two decades have witnessed important advances in the mathematical and statistical analysis of dynamic systems particularly in physics epidemiology and meteorology many of these developments have already found their way into economics and

ems exchange rate bands a monte carlo investigation of three target zone models abstract a monte carlo analysis is used to compare three target zone models in reproducing some stylized facts of weekly deutsche mark exchange rates in the european monetary system for the period january 1987 august 1992 the models are the standard target zone model a model of infracum intramarginal interventions and a model of unfulfilled realignment expectations compared with the corresponding dollar rates returns on deutsche mark rates exhibit much more non normality which can be generated endogenously by the latter two models and more conditional heteroskedasticity which can be produced simultaneously by the infra cum intramarginal interventions model

combining time variation and mixed frequencies an analysis of government spending multipliers in italy summary in this paper we propose a time varying parameter vector autoregression var model with stochastic volatility which allows for estimation on data sampled at different frequencies our contribution is twofold first we extend the methodology developed by cogley and sargent drifts and volatilities monetary policies and outcomes in the post wwii u s review of economic studies 2005 8 262 302 and primiceri time varying structural vector autoregressions and monetary policy review of economic studies 2005 72 821 852 to a mixed frequency setting in particular our approach allows for the inclusion of two different categories of variables high frequency and low frequency into the same time varying model second we use this model to study the macroeconomic effects of government spending shocks in italy over the 1988 q4 2013 q3 period italy as well as most other euro area economies is characterized by short quarterly time series for fiscal variables whereas annual data are generally available for a longer sample before 1999 our results show that the proposed time varying mixed frequency model improves on the performance of a simple linear interpolation model in generating the true path of the missing observations second our empirical analysis suggests that government spending shocks tend to have positive effects on output in italy the fiscal multiplier which is maximized at the 1 year horizon follows a u shape over the sample considered it peaks at around 1 5 at the beginning of the sample it then stabilizes between 0 8 and 0 9 from the mid 1990s to the late 2000s before rising again to above unity during the recent crisis copyright 2015 john wiley sons ltd

dollar jump fears 1984 1992 distributional abnormalities implicit in currency futures options abstract deutsche mark and yen futures options over 1984 1992 and 1986 1992 respectively are examined for deviations from the lognormal assumption underlying standard option pricing models two methods are used an atheoretic skewness premium and daily estimates of moments using a model for pricing american foreign currency futures options under systematic exchange rate jump risk substantial variation over time is found in all moments including implicit skewness and kurtosis the implicit abnormalities predict future abnormalities in log differenced dm futures prices but not yen the peso problem implications do not explain standard rejections of uncovered interest parity

option pricing and implicit volatilities abstract this paper demonstrates that black scholes implied volatilities can be used to value options in many situations where the assumptions of the black scholes model are violated including i alternative stock processes ii stochastic interest rates and iii market frictions given its computational simplicity this procedure provides an attractive alternative to the more complex models with a direct estimation procedure

fundamentals uncertainty bubbles and exchange rate dynamics abstract using a monetary model of exchange rate determination we study exchange rate dynamics with bubbles which depend on stochastic market fundamentals these dynamics can be either stochastically stable or unstable and either monotonic or non monotonic including cyclic in an extreme case they converge with probability one and exhibit cyclic movements implications for the analysis of time dependent regime shifts are also explored exchange rates with bubbles are likely to appear less volatile than the fundamentals in finite samples both the variance bounds and cointegration tests might thus be ineffective in testing the absence of bubbles under fundamentals uncertainty

exchange rate discounting abstract economists often describe nominal exchange rates as forward looking so that they reflect discounted expected future fundamentals this study applies a method for identifying the discount rate involved without knowing or measuring fundamentals identification arises from assumptions on the stochastic process followed by fundamentals combined with non linearity arising from expected future regime changes two applications yield evidence against the present value model in the form of discount rates which are negative and statistically significant

empirical features of the second generation target zone models mean reverting fundamentals and endogenous devaluation risk we show that within bertola and svensson s second generation target zone model mean reverting interventions and endogenous devaluation risk are closely interrelated over the period 1983 93 we analyze the degree of mean reversion in the underlying fundamental process as well as the term structure of interest rate differentials vis a vis germany for six exchange rate mechanism currencies for austria denmark and the netherlands and for belgium after 1990 our estimates are broadly in line with the first generation target zone model whereas those for france and italy are in accordance with the model that allows for endogenous devaluation risk jel f31 e43