the out of sample success of term structure models as exchange rate predictors a step beyond abstract a large literature suggests that standard exchange rate models cannot outperform a random walk forecast and that the forward rate is not an optimal predictor of the spot rate however there is evidence that the term structure of forward premia contains valuable information for forecasting future spot exchange rates and that exchange rate dynamics display nonlinearities this paper proposes a term structure forecasting model of exchange rates based on a regime switching vector equilibrium correction model which is novel in this context our model significantly outperforms both a random walk and to a lesser extent a linear term structure vector equilibrium correction model for four major dollar rates across a range of horizons

a deterministic inventory model for deteriorating items with stock dependent demand rate abstract a deterministic inventory model is developed by assuming that the demand rate is stock dependent and the items deteriorate at a constant rate the expression for the average net profit over one production run is derived and its optimization with respect to the decision variables q initial stock and t duration of a production cycle is carried out this leads to two highly nonlinear equations which are solved by using a subroutine neqnf in imsl math library in cyber 180 480a computer system the optimal solution so derived is compared with that for the no deterioration 0 case sensitivity of the optimal solution to changes in parameter values is examined several aspects of the functional form for the demand rate are considered in a separate section finally the salient features of the problem and its solution are discussed in brief

a theory of corporate financial decisions with liquidity and solvency concerns this paper studies the impact of both liquidity and solvency concerns on corporate finance i present a tractable model of a firm that optimally chooses capital structure cash holdings dividends and default while facing cash flows with long term uncertainty and short term liquidity shocks the model explains how changes in solvency affect liquidity and also how liquidity concerns affect solvency via capital structure choice these interactions result in a dynamic cash policy in which cash reserves increase in profitability and are positively correlated with cash flows the optimal dividend distributions implied by the model are smoothed relative to cash flows i also find that liquidity concerns lead to a decrease of dispersion of credit spreads

financial contracting theory meets the real world an empirical analysis of venture capital contracts we compare the characteristics of real world financial contracts to their counterparts in financial contracting theory we do so by studying the actual contracts between venture capitalists vcs and entrepreneurs the distinguishing characteristic of vc financings is that they allow vcs to separately allocate cash flow rights board rights voting rights liquidation rights and other control rights we describe and measure these rights we then interpret our results in relation to existing financial contracting theories we also describe the interrelation and the evolution across financing rounds of the different rights query 1 query 2

inventory policy with time dependent setup cost abstract assume a time interval t is given moreover assume that the setup cost is not constant but varies with the lapse of time our problem is to determine the inventory policy for the given t how often the order is placed during t and how much is ordered at each ordering time point are our main themes we solve these problems in the following ways if frequency of orders for t is given arbitrarily the ordering policy is to be planned by using the techniques of dp by choosing a proper frequency of orders so that it may minimize the total inventory cost required during t an optimal inventory policy for t is determined moreover by applying dp some mathematical properties of this policy are examined even if exact mathematical expressions for frequency of orders and inventory cost are determined their values are obtained these become the merit of applying dp

limited liability and incentive contracting with ex ante action choices abstract this article examines a principal agent model of financial contracting in which a risk neutral entrepreneur agent makes an unobservable ex ante effort choice while employing the investment funds of a risk neutral investor principal the key innovation is that the investment contract is subject to statutory liability limits given these liability limits two settings are considered one in which the investor payoff function is also constrained to be monotonically nondecreasing in firm profit and another in which no such monotonic contract constraint is imposed in the former case a standard debt contract is shown to emerge and a first best effort choice is not achieved in the latter setting the optimum is characterized by a live or die payoff function and a first best effort level may or may not be realized

maintaining optimal inventory level by feedbacks abstract in this paper the inventory level is examined under a situation in which the demand function consists of two parts one which is sometimes referred to as the trend of demand is described as a proper polynomial function of time the other is given as a random variable with a finite variance a policy is planned which is to bring the expected value of realized inventory level to the planned level in order to accomplish this purpose some feedbacks are to be introduced the first feedback is realized by estimating the demand level in the future based upon the demand level in the past how much data is necessary depends on the degree of the polynomial function to be estimated the second is obtained by monitoring the realized inventory level the difference between the realized inventory level and the planned level is used as a feedback we will show that by combining these two feedbacks the expected value of difference between two inventory levels planned and realized converges to zero

environmental tax policy and intergenerational distribution abstract we study the effects of environmental taxation within the context of an overlapping generations model the quality of the environment is modelled as a durable consumption good introduction of the environmental tax harms old existing generations and benefits young existing generations as well as all future generations increasing the tax in a pareto improving manner is easier the higher the pre existing tax the reverse holds if tax policy is decided by majority rule a suitably designed bond policy can be used to redistribute the efficiency gains due to the internalisation of environmental externalities across the generations

currency internationalization and valuation effects based on the threshold model based on the three functions of currency internationalization including exchange medium pricing currency and foreign reserve this paper explores how the degree of currency internationalization a

should central bankers talk to the foreign exchange markets in this paper we study the role of official statements and speeches given by central bank authorities in charge of foreign exchange policy we investigate the impact of statements that comment on and confirm such interventions on the day of the intervention on the two major foreign exchange markets over an extended period 1989 2003 we also study the impact in terms of policy effectiveness of central bank communication before the actual operations our results suggest that appropriate speeches clarifying the current intervention policy can have marginally virtuous effects both in terms of exchange rate level and exchange rate volatility this leads us to conclude that in general actual interventions on the market should still be employed provided that official statements are used to clarify the nature and purpose of these interventions c 2008 elsevier ltd all rights reserved

potential pitfalls for the purchasing power parity puzzle sampling and specification biases in mean reversion tests of the law of one price the ppp puzzle is based on empirical evidence that international price differences for individual goods loop or baskets of goods ppp appear highly persistent or even nonstationary the present consensus is these price differences have a half life that is of the order of five years at best and infinity at worst this seems unreasonable in a world where transportation and transaction costs appear so low as to encourage arbitrage and the convergence of price gaps over much shorter horizons typically days or weeks however current empirics rely on a particular choice of methodology involving i relatively low frequency monthly quarterly or annual data and ii a linear model specification in fact these methodological choices are not innocent and they can be shown to bias analysis towards findings of slow convergence and a random walk intuitively if we suspect that the actual adjustment horizon is of the order of days then monthly and annual data cannot be expected to reveal it if we suspect arbitrage costs are high enough to produce a substantial band of inaction then a linear model will fail to support convergence if the process spends considerable time random walking in that band thus when testing for ppp or loop model specification and data sampling should not proceed without consideration of the actual institutional context and logistical framework of markets

the liability insurance market t his paper offers an overview of the u s liability insurance market and the link between its performance and developments in tort law over the last few decades the dominant feature of the insurance market has been the intermittent periods of rapidly rising premiums and cutbacks on the availability of coverage the insurance cycle appears to be increasing in amplitude and since the 1960s has been concentrated increasingly in liability lines an episode of rising premiums in the late 1960s was followed by a six year period of declining and eventually negative growth rates in total liability insurance premiums over the 1975 1977 period the annual growth rate jumped to 30 percent then followed another period of declining real premiums until premiums nearly tripled in 1984 1986 accompanied by cancellations of policies and massive withdrawal of insurers from some lines this crisis had an economic impact beyond the insurance market leading to the withdrawal of many goods and services from u s markets in mid 1987 the market began to turn again with premiums falling by as much as 40 percent for some commercial policies since then aggregate revenue from premiums has been relatively stable the liability insurance market is intertwined with the tort system in addition to providing incentives to avoid accidents the tort system allocates the risks of accident costs in providing compensation for accident victims the modern expansion of liability in tort law as described by priest in this issue represents a shift in the burden of supplying insurance from first party insurance markets to liability or third party insurance markets clearly this shift will

how liable should a lender be the case of judgment proof firms and environmental risk comment recently u s environmental law has shown a tendency toward increased lender liability a model of a potentially judgment proof owner of a firm a lender and a potential victim is developed in which this policy can increase accident frequency and reduce efficiency full partial and zero lender liability rules and a minimum equity requirement are analyzed partial lender liability and an equivalent minimum equity requirement deliver the highest level of efficiency although the former can deliver a higher contribution by the lender to the victim than the latter policy and empirical implications are also discussed copyright 1995 by american economic association

central bank interventions and exchange rate band regimes abstract this paper presents an endogenous switching regression model for the exchange rate process where the switch is defined by the central bank criteria functions for intervening we study the signal effect of interventions on the exchange rate using norwegian daily data on official interventions we first find that interventions seemed to have been more effective in moving the exchange rate in the expected desired direction in the regime when the exchange rate was kept away from the edges of the band this type of intervention regime also reduces significantly the conditional volatility of the exchange rate thus when the exchange rate was near the weakest edge of the currency band its conditional variance was significantly larger than when it was moving around its central parity finally we show that in order to obtain consistent estimates intervention variables cannot enter as exogenous variables in the conditional mean or conditional variance of the exchange rate

are exchange rate bands better than fixed exchange rates the imported credibility approach this paper explicitly incorporates exchange rate bands into the barro gordon model of inflation this is a non trivial extension focusing on markov perfect equilibria we specify the properties of the optimal policy functions exchange rate dynamics and hence the arguments for and against target zones the attractiveness of alternative exchange rate regimes i e fixed flexible and target zones and the position of exchange rates inside the band depend on the inflationary performance of the center country

financial integration and the wealth effect of exchange rate fluctuations abstract recent years have witnessed a large increase in international financial integration in the form of largely offsetting cross holdings across countries we assess how such financial leverage affects the international transmission of monetary shocks and find that it leads to sizable welfare differentials that far exceed the impact due to nominal rigidities we document the relevance of the exact nature of holdings with bond holdings associated with larger effects than equity holdings the impact of financial leverage on welfare is also sensitive to the extent of exchange rate pass through and the substitutability between goods produced in different countries

dynamic prudential regulation is prompt corrective action optimal the current u s bank capital regulation features prompt corrective action which mandates regulators to intervene in and liquidate banks based on their book value capital ratios to see if prompt corrective action is optimal i build a dynamic model of repeated interactions between a banker and a regulator under hidden choice of risk private information on returns and limited commitment by the banker and costly liquidation i first characterize the optimal incentive feasible allocation i then demonstrate that the optimal allocation is implementable through the combination of a risk based deposit insurance premium and a book value capital regulation with stochastic liquidation

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

multivariate cointegration analysis and the long run validity of ppp this paper tests the long run validity of ppp using johansen s multivariate cointegration methodology on exchange rates and domestic and foreign price levels monthly data covering the recent flexible exchange rate period of the dm vis a vis 15 currencies le ad to the following conclusion ppp seems to hold in the long run for s ix european currencies the pound lira norwegian krone schilling escudo and peseta however ppp has to be rejected for the united states and the canadian dollar as well as for the belgian franc and the danish krone nevertheless the authors analysis is more favorable to ppp as a long run property of exchange rates than the recent work applying the engle granger regression methodology copyright 1993 by mit press

from eoq towards zi zero inventory zi is a new and powerful concept to improve production efficiency underpinning zi is set up reduction and this paper examines what eventuates when set up costs are cut the folklore is that set up reduction lowers inventory and costs we obtain results contrary to that reducing set up costs need not reduce inventory for example likewise lowering set up costs need not necessarily lower total production and inventory costs furthermore most investments produce marginally decreasing returns set up cost reduction prompts the opposite it produces marginally increasing not decreasing returns a parametric algorithm that calculates the benefit of set up cost reduction is provided most presentations of zi have been descriptive with very few mathematical models of it yet untaken by modeling certain zi concepts mathematically we scrutinize their validity and sometimes invalidity

central bank secrecy in the foreign exchange market abstract this paper argues that with sticky goods prices and a forward looking exchange rate the central bank will only want a partial dissemination of its information about shocks to the economy it is shown that in such a model the central bank may prefer to intervene secretly in the foreign exchange markets when responding in anticipation of future shocks but openly when reacting to current shocks the model thus provides a rationale for secrecy in central bank foreign exchange operations the model also elucidates the relationship between the signaling and portfolio balance channels of sterilized intervention

aggregate spending and the terms of trade is there a laursen metzler effect this paper investigates the spending and current account effects of terms of trade shifts in a model where households maximize utility over an infinite planning period in the framework developed here an economy specialized in production must experience a fall in aggregate spending and a current surplus as a result of an unanticipated permanent worsening in its terms of trade the paper s model thus provides a setting in which the current account deficit predicted by laursen and metzier harberger and others fails to materialize

real and nominal exchange rates in the long run an empirical investigation abstract this paper reports on econometric tests of the hypothesis that purchasing power parity holds as a long run relationship using data on eight industrialized countries during the flexible exchange rate period the empirical work proceeds by i testing whether nominal exchange rates and relative price levels are co integrated and ii conducting impulse response analysis of long run exchange rate and relative price level changes to explain the data keynesian models suggest that shocks during the estimation period were due principally to exogenous shifts in aggregate demand while equilibrium models suggest that monetary factors have been relatively more important

what prompts japan to intervene in the forex market a new approach to a reaction function abstract this paper estimates and analyzes the reaction function of japanese intervention in the foreign exchange forex markets using daily japanese intervention data from april 1 1991 to december 31 2002 a theoretical friction model is adopted to describe the intervention as cost minimizing behavior an ordered probit model consistent with the theoretical model is employed to estimate authorities reaction function a noise to signal ratio is applied in selecting the optimal cutoff point in estimated ordered probit function major findings are as follows 1 a regime change in june 1995 from small scale frequent interventions to large scale infrequent interventions is detected 2 the optimum cutoff is higher in the first half than the second half

structural breaks in taylor rule based exchange rate models evidence from threshold time varying parameter models in this note we develop a taylor rule based empirical exchange rate model for eleven major currencies that endogenously determines the number of structural breaks in the coefficients using a constant parameter specification and a standard time varying parameter model as competitors reveals that our flexible modeling framework yields more precise density forecasts for all major currencies under scrutiny over the last 24 years

the eoq models modified by introducing discount of purchase price or increase of setup cost abstract the eoq model of inventory problem can determine ordering cycle and quantity when the purchase unit price is constant ordering cycle and ordering quantity which minimize the one day s average inventory cost is not dependent on the purchase price but if purchase price may change the eoq model must be modified the purchase unit price is discounted as the ordering becomes larger the discount of purchase price is described with a decreasing function of ordering quantity this function is not always continuous with respect to the ordering quantity under this condition one day s average profit can be defined and we can determine ordering cycle and ordering quantity which maximize one day s average profit moreover we consider the situations under which the setup cost depends on the ordering quantity in this case the setup can be described with the increasing function of ordering quantity we show that the eoq model can be applied if it is modified by introducing the continuous setup cost function this function is not differentiable at some levels of ordering quantity

a macroeconomic model with a financial sector this paper studies a macroeconomic model in which financial experts borrow from less productive agents we pursue four sets of results i the economy is prone to instability and occasionally enters volatile episodes as volatility spikes agents precautionary motive increases depressing prices even further log linear approximations fail to capture these non linear effects that can cause economies to be significantly depressed for long periods of time ii endogenous risk during volatile episodes increases asset price correlations iii financial experts impose a negative externality on each other and on the labor sector by not maintaining adequate capital cushion and funding structure iv while risk sharing within the financial sector through securitization and derivatives contracts reduces many inefficiencies it can also amlify systemic risks

dynamic security design convergence to continuous time and asset pricing implications an entrepreneur with limited liability needs to finance an infinite horizon investment project an agency problem arises because she can divert operating cash flows before reporting them to the financiers we first study the optimal contract in discrete time this contract can be implemented by cash reserves debt and equity the latter is split between the financiers and the entrepreneur and pays dividends when retained earnings reach a threshold to provide appropriate incentives to the entrepreneur the firm is downsized when it runs short of cash we then study the continuous time limit of the model we prove the convergence of the discrete time value functions and optimal contracts our analysis yields rich implications for the dynamics of security prices stock prices follow a diusion reflected at the dividend barrier and absorbed at zero their volatility as well as the leverage ratio of the firm increase after bad performance stock prices and book tomarket ratios are in a non monotonic relationship a more severe agency problem entails lower price earning ratios and firm liquidity and higher default risk

real exchange rate behavior the recent float from the perspective of the past two centuries using annual data spanning two centuries for dollar sterling and franc sterling real exchange rates we find strong evidence of mean reverting real exchange rate behavior using simple stationary autoregressive models estimated on prefloat data we easily outperform nonstationary real exchange rate models in dynamic forecasting exercises over the recent float such stationary univariate equations explain 60 80 percent of the in sample variation in real exchange rates although the degree of short run persistence may be high the econometric estimates imply a half life of shocks to the real exchange rate of about 6 years for dollar sterling and a little under 3 years for franc sterling

on the welfare benefits of an international currency abstract is it beneficial for a country s currency to be used internationally and if so can we quantify the benefit since the emergence of the euro there has been great interest in the consequences of a transfer of the dollar s premier international role to the euro this paper presents a novel model based approach towards assessing the welfare benefits associated with the international use of a country s currency apart from the familiar benefits associated with seigniorage residents of the issuing country experience an increase in the purchasing power of their currency both at home and abroad in the calibration exercise carried out in this paper we find the benefits of an international currency to be quantitatively significant the welfare gain for the euro area in having the euro internationally used ranges from 1 9 to 2 3 of consumption depending on relative inflation rates the rest of the world is not indifferent as to which currency circulates as the dominant international currency conditional on their currency not being used internationally their preference is for the dominant international currency to be the one with the lowest inflation rate

a nonlinear stochastic rational expectations model of exchange rates abstract this paper constructs an example of a nonlinear stochastic rational expectations exchange rate with an explicit solution which is consistent with nonlinearities in short term movements in exchange rates the model consists of risk neutral agents who know the intervention rule of the central bank the resulting exchange rate switches between two linear stochastic processes one when intervention is present and another when intervention is absent nonlinearity enters through the probability of intervention which is time varying and depends on past outcomes this model is consistent with the empirical observations that the rate of change of the exchange rate has little autocorrelation but it exhibits strong nonlinear dependence and its variance changes over time jel j31 g15

optimal security design and dynamic capital structure in a continuous time agency model we derive the optimal dynamic contract in a continuous time principal agent setting and implement it with a capital structure credit line long term debt and equity over which the agent controls the payout policy while the project s volatility and liquidation cost have little impact on the firm s total debt capacity they increase the use of credit versus debt leverage is nonstationary and declines with past profitability the firm may hold a compensating cash balance while borrowing at a higher rate through the credit line surprisingly the usual conflicts between debt and equity asset substitution strategic default need not arise in this paper we consider a dynamic contracting environment in which a riskneutral agent or entrepreneur with limited resources manages an investment activity while the investment is profitable it is also risky and in the short run it can generate arbitrarily large operating losses the agent will need outside financial support to cover such losses and continue the project the difficulty is that while the probability distribution of the cash flows is publicly known the agent may distort these cash flows by taking a hidden action that leads to a private benefit specifically the agent may i conceal and divert cash flows for his own consumption and or ii stop providing costly effort which would reduce the mean of the cash flows therefore from the perspective of the principal or investors that fund the project there is the concern that a low cash flow realization may be a result of the agent s actions rather than the project s fundamentals to provide the agent with appropriate incentives investors control the agent s wage and may also withdraw their financial support for the project and force its early termination we seek to characterize an optimal contract in this framework and relate it to the firm s choice of capital structure we develop a method to solve for the optimal contract given the incentive constraints in a continuous time setting and study the properties of the credit line debt and equity that implement the contract as in the discrete time model of demarzo and fishman 2003 the continuous time setting offers several peter m demarzo is from stanford university and yuliy sannikov is from u c berkeley we

optimal central bank intervention in the foreign exchange market abstract we consider a currency with exchange rate dynamics modeled as a geometric brownian motion the objective of the central bank is to keep this exchange rate as close as possible to a given target so there is a running cost associated to the difference between the exchange rate and the target additionally there are also fixed and proportional costs associated with each intervention the objective of this paper is to find the optimal level of intervention and the optimal sizes of the interventions so as to minimize the total cost we solve this problem by applying the theory of stochastic impulse controls journal of economic literature classification numbers c61 d81 f31 g15

performance pricing in bank debt contracts abstract performance pricing links bank debt interest rate spreads to a borrower s performance via two options interest decreasing performance pricing reduces spreads if credit quality improves it is more common when prepayment is more likely or costly and when adverse selection costs are higher and is less common when multiple performance measures better predict credit quality interest increasing performance pricing increases spreads if credit quality deteriorates it is more common when lenders reduce interest rates to add this provision when downgrades are more likely and when moral hazard costs are higher we find lower spreads for contracts with interest increasing performance pricing

consumption pollution tradeoffs in an environment vulnerable to pollution related catastrophic collapse abstract this paper considers the consequences of an avoidable risk of irreversible environmental catastrophe for society s optimal long run consumption pollution tradeoffs the risk is assumed to be a nondecreasing function of pollution concentration which evolves as a dynamic environmental renewal process the main objective of the paper is to derive qualitative insights regarding the effects of such risk on optimal management

long run purchasing power parity is it for real in this paper we re examine the purchasing power parity concept using data from the recent experience with floating exchange rates in particular we utilise the recently developed multivariate cointegration methodology to test for a long run relationship between exchange rates and relative prices and also to test for the proportionality of the exchange rate with respect to relative prices in contrast to much other research we demonstrate that there is a long run relationship between a number of bilateral u s dollar exchange rates and their corresponding relative prices the proportionality of the exchange rate to relative prices does not however receive support from the data this finding may be attributable to the use of measured price series rather than the true series

a model of capital and crises we develop a model in which the capital of the intermediary sector plays a critical role in determining asset prices the model is cast within a dynamic general equilibrium economy and the role for intermediation is derived endogenously based on optimal contracting considerations low intermediary capital reduces the risk bearing capacity of the marginal investor we show how this force helps to explain patterns during financial crises the model replicates the observed rise during crises in sharpe ratios conditional volatility correlation in price movements of assets held by the intermediary sector and fall in riskless interest rates

the impact of fx central bank intervention in a noise trading framework abstract in this paper we analyse the effectiveness of the direct central bank interventions using a new effectiveness criterion to this aim we investigate the effects of central bank interventions cbi in a noise trading model with chartists and fundamentalists we first estimate a model in which chartists extrapolate past returns and fundamentalists forecast a mean reverting dynamics of the exchange rate towards a fundamental value then we investigate the role of central bank interventions for explaining the switching properties between the two types of agents we find evidence that in the medium run interventions increase the proportion of fundamentalists and therefore exert some stabilizing influence on the exchange rate

dividends safety and liquidation when liabilities are long term and stochastic abstract this paper investigates the optimal management of a firm faced with a long term liability that occurs at a random date three issues are analysed the optimal dividend policy optimal expenditure on safety to delay the occurrence of the liability and the optimal liquidation date of the firm an owner faced with dynamic unlimited liability never liquidates and therefore accumulates capital to the golden rule level for long term liabilities dividend payments and safety expenditure are non decreasing over time the owner protected by limited liability may liquidate the firm in finite time in order to avoid paying the liability if this is the case then it accumulates less capital than the dynamic unlimited liability owner and may decrease dividend payments and safety expenditure over time the paper shows that a finite liquidation date is more likely to be optimal when the arrival rate of the liability occurrence increases over time

large risks limited liability and dynamic moral hazard we study a continuous time principal agent model in which a risk neutral agent with limited liability must exert unobservable effort to reduce the likelihood of large but relatively infrequent losses firm size can be decreased at no cost or increased subject to adjustment costs in the optimal contract investment takes place only if a long enough period of time elapses with no losses occurring then if good performance continues the agent is paid as soon as a loss occurs payments to the agent are suspended and so is investment if further losses occur accumulated bad performance leads to downsizing we derive explicit formulae for the dynamics of firm size and its asymptotic growth rate and we provide conditions under which firm size eventually goes to zero or grows without bounds

target zones and realignments recent contributions emphasize that the presence of exchange rate target zones has important effects on the within band behavior of exchange rates when agents are forward looking the authors find that the implications of available models are inconsistent with european exchange rate data and they suggest that the frequent realignments occurring in the period they consider may be responsible for this they construct a model in which the likelihood of a realignment in the near future increases as the exchange rate approaches the limits of its fluctuation band and show that its implications are broadly consistent with the evidence copyright 1992 by american economic association

investigating nonlinearities in real exchange rate adjustment threshold cointegration and the dynamics of exchange rates and relative prices abstract motivated by growing evidence of nonlinear mean reverting behavior in real exchange rates this paper investigates the underlying dynamics in the context of a threshold vector error correction model tvecm of nominal exchange rate and relative prices unlike univariate models our nonlinear multivariate framework takes into explicit account the joint behavior and individual dynamics of the nominal exchange rate and relative prices when these two key variables are threshold cointegrated our empirical application unravels their relative contribution to mean reversion and underscores the importance of capturing their interactions in investigating the nonlinear adjustment toward purchasing power parity

central bank intervention and foreign exchange rates new evidence from figarch estimations abstract in this paper we investigate the effects of official interventions on the short run evolution and volatility of exchange rates to this aim we rely on a new measure of volatility implied by the figarch model that outperforms the traditionally used garch one it is found that central bank interventions exert an incorrectly signed effect on the levels of exchange rates and tend to increase their volatility in the short run in general our results also show that the traditional garch estimations tend to underestimate the effects in terms of volatility

dynamic contracts with moral hazard and adverse selection we study a novel dynamic principal agent setting with moral hazard and adverse selection persistent as well as repeated in the model an agent whose skills are his private information faces a finite sequence of tasks one after the other upon arrival of each task the agent learns its level of difficulty and then chooses whether to accept or refuse each task in turn and how much effort to exert although his decision to accept or refuse a task is publicly known the agent s effort level is his private information we characterize optimal contracts and show that the per period utility of the agent approaches his per period utility when his skills are publicly known as the discount factor and the time horizon increase

production inventory models for a damageable item with variable demands and inventory costs in an imperfect production process in this paper economic production quantity epq models for breakable or deteriorating item are developed with variable demands being dependent on time or on hand stock here rate of production and holding cost are time dependent unit production cost is a function of both production reliability indicator and production rate set up cost is also partially production rate dependent the production process produces some imperfect quantities which are instantly reworked at a cost to bring back those units to the perfect ones the production process ultimately depends on both time and reliability indicator the models are formulated as optimal control problems and the total profit functions with effect of inflation and time value of money are expressed as finite integrals over the finite planning horizon the problems are solved using euler lagrange function based on variational calculus and newton raphson method to determine the optimal production reliability indicator r and then corresponding production rates and total profits in some cases results of the models for deteriorating item are obtained as particular cases from those of breakable item models similarly results of simple epq models without damageability are deduced as particular cases numerical experiments are performed to illustrate the models both numerically and graphically

occasional interventions to target rates this paper develops a model of central bank intervention based upon a policy characteristic of foreign exchange interventions by the united states germany and japan in the late 1980 s and evaluates it empirically central bankers intervene with greater intensity as rates deviate from target levels but they also try to stabilize rates around current levels the model is estimated using exchange rates and data based upon observed central bank interventions interestingly the estimates of the model are consistent with the predictions of the theoretical model for both the deutsche mark dollar rate and less strongly for the yen dollar rate jel f41 g15 f31

a theory of financing constraints and firm dynamics there is widespread evidence supporting the conjecture that borrowing constraints have important implications for firm growth and survival in this paper we model a multiperiod borrowing lending relationship with asymmetric information we show that borrowing constraints emerge as a feature of the optimal long term lending contract and that such constraints relax as the value of the borrower s claim to future cash flows increases we also show that the optimal contract has interesting implications for firm dynamics in agreement with the empirical evidence as age and size increase mean and variance of growth decrease and firm survival increases

liability and large scale long term hazards this paper analyzes the application of liability to large scale long term hazards the key features distinguishing such hazards are the long temporal separation between exposure to a hazard and disease and the large damages when injuries finally emerge the large scale of damages creates a strong incentive to avoid liability payments and the long temporal separation creates numerous avenues through which parties can avoid paying possible damage awards the analysis focuses on the incentive to avoid paying damages by vertically divesting production tasks associated with serious occupational risks such divestiture can lower liability costs if the small firm operating the risky stage goes out of business before latent injuries emerge or has insufficient assets to pay damages and declares bankruptcy when suits are filed the paper then presents an empirical regression analysis of small firm entry into the u s economy between 1967 and 1980 the period in which liability laws were changing the point estima

a panel project on purchasing power parity mean reversion within and between countries abstract previous time series studies have shown evidence of mean reversion in real exchange rates deviations from purchasing power parity ppp appear to have half lives of approximately four years however the long samples required for statistical significance are unavailable for most currencies and are potentially inappropriate because of regime changes in this study we re examine deviations from ppp using a panel of 150 countries and 45 annual post wwii observations our panel shows strong evidence of mean reversion that is similar to that from long time series ppp deviations are eroded at a rate of approximately 15 annually i e their half life is around four years such findings can be masked in time series data but are relatively easy to find in cross sections

the external wealth of nations measures of foreign assets and liabilities for industrial and developing countries abstract although capital flows are closely monitored surprisingly little is known about the accumulated stocks of foreign assets and liabilities held by various countries especially in the developing world this paper constructs estimates of foreign assets and liabilities and their equity and debt subcomponents for a sample of 67 industrial and developing countries it characterizes the stylized facts of international balance sheets and asks whether there are trends in net foreign asset positions and shifts in debt equity ratios over time finally it explores the sensitivity of estimated stock positions to the treatment of valuation effects not captured in balance of payments data

micro macro and strategic forces in international trade invoicing synthesis and novel patterns abstract the currency used in invoicing international trade matters for the impact of exchange rate movements in the presence of price rigidities we present stylized facts on specific macro micro and other drivers of invoicing based on 45 million canadian import transactions four main results emerge first a large share of invoicing takes place in vehicle currencies that are neither the exporters nor the importers second we document a novel link between the size of individual transactions and invoicing both the absolute value of a transaction and its relative size at the industry level matter third the exchange rate plays an important role along three dimensions exchange rate volatility exchange rate regime and currency transaction volumes in foreign exchange markets finally we confirm the role of the market share of an exporting country at the industry level our results identify the most salient patterns in order to guide further developments in theoretical models of invoicing currency choice

long run purchasing power parity during the recent float abstract this paper examines the relevance of long run purchasing power parity ppp which allows for measurement errors during the recent floating exchange rate period previous empirical studies generally fail to find support for long run ppp over this period in this paper in this paper the cointegration property of exchange rates and prices is examined using maximum likelihood procedure and we find significant evidence favorable to long run ppp further tests for symmetry and proportionality indicate that these two conditions are not generally with the data the results support the hypothesis of long run ppp with measurement errors in prices

market frictions and real exchange rates abstract one explanation for the failure of purchasing power parity ppp is that market frictions impede trade allowing departures from ppp to grow quite large without precipitating goods arbitrage if this explanation is correct then other things equal large deviations from ppp should be less persistent than small differences this paper examines this prediction over the modern floating rate era the outcome is surprising between most countries large deviations from ppp appear to be at least as persistent as small deviations and perhaps even more so the exceptions are for some intra ec real exchange rates the implication is that market frictions alone do not explain the chimerical nature of ppp

central bank intervention and exchange rate volatility abstract this paper explores the effects of foreign exchange intervention by central banks on the behavior of exchange rates the g 3 central banks have undertaken an unprecedented number of both coordinated and unilateral intervention operations in the last 10 years existing empirical evidence on the effectiveness of intervention is mixed studies using data from the 1970s suggest that intervention operations that do not affect the monetary base have at most a short lived influence on exchange rates but more recent studies indicate that the intervention operations that followed the plaza agreement influenced both the level and variance of exchange rates this paper examines the effects of us german and japanese monetary and intervention policies on dollar mark and dollar yen exchange rate volatility over the 1977 1994 period the results indicate that intervention operations generally increase exchange rate volatility this is particularly true of secret interventions which are those undertaken by central banks without notification of the public overt interventions in the mid 1980s appear to have reduced exchange rate volatility but in other periods and for the 1977 1994 period as a whole central bank intervention is associated with greater exchange rate volatility

optimal lending contracts and firm dynamics we develop a general model of lending in the presence of endogenous borrowing constraints borrowing constraints arise because borrowers face limited liability and debt repayment cannot be perfectly enforced in the model the dynamics of debt are closely linked with the dynamics of borrowing constraints in fact borrowing constraints must satisfy a dynamic consistency requirement the value of outstanding debt restricts current access to short term capital but is itself determined by future access to credit this dynamic consistency is not guaranteed in models of exogenous borrowing constraints where the ability to raise short term capital is limited by some prespecified function of debt we characterize the optimal default free contract which minimizes borrowing constraints at all histories and derive implications for firm growth survival leverage and debt maturity the model is qualitatively consistent with stylized facts on the growth and survival of firms comparative statics with respect to technology and default constraints are derived borrowing constraints are an important determinant of firm growth and survival 1 such constraints may arise in connection to the financing of investment opportunities faced by firms or temporary liquidity needs such as those required to survive a recession this paper develops a theory of endogenous borrowing constraints and studies its implications for firm dynamics in our model debt is constrained by the firm s limited liability and option to default a lending contract specifies an initial loan size future financing and a repayment schedule the choice of these variables in turn determines future growth the firm s future borrowing capacity and its ability and willingness to repay hence borrowing constraints and firm dynamics are jointly determined we study this dynamic design problem our model builds on thomas and worral s 1994 model of foreign direct investment at time zero a risk neutral borrower firm or entrepreneur has a project which requires a fixed initial set up cost every period the project yields revenues that increase with the amount of 1 there is considerable evidence suggesting that financing constraints are important determinants of firm dynamics gertler and gilchrist 1994 argue that liquidity constraints may explain why small manufacturing firms respond more to a tightening of monetary policy than do larger manufacturing firms perez quiros and timmermann 2000 show that in recessions smaller firms are more sensitive to the worsening of credit market conditions as measured by higher interest rates and default premia evans and jovanovic 1989 show that the liquidity constraints are essential in the decision to become an entrepreneur fazzari hubbard and petersen 1988 among others view financial constraints as an explanation for the dynamic behaviour of aggregate investment and cabral and mata 1996 are able to fit reasonably well the size distribution of portuguese manufacturing firms by estimating a simple model of financing constraints for surveys see hubbard 1998 and stein 2003

investing in reduced setups in the eoq model this paper is motivated by the observation that the japanese have devoted much time and energy to decreasing setup costs in their manufacturing processes and that there has been little in the way of a formal framework available to use to think about such efforts the object of this paper is to begin to provide such a framework the framework developed identifies only one aspect of the advantages of reducing setups namely reduced inventory related operating costs the other advantages such as improved quality control flexibility and increased effective capacity are not accounted for in this paper nevertheless substantial reductions in setups may be warranted based solely on the benefits identified in this paper the approach taken here introduces an investment cost associated with changing the current setup level and adds a per unit time amortization of this cost to the other costs identified in the standard eoq model the general problem becomes that of minimizing the sum of a convex and a concave function in two special cases the minimization can be carried out explicitly in one of these cases numerous interpretations of the results are made including comparisons of japanese and american practices for example holding other parameters constant there is a critical sales level such that investment is made in reducing setups if and only if the sales rate is above that level when such investment is made the optimal lot size is independent of the sales rate the paper also addresses the joint selection of the setup cost and the sales rate selection of the sales rate is seen as incorporating explicit production and holding costs into the classical monopolist s pricing problem an explicit solution is obtained for the model postulated

aggregation and linearity in the provision of intertemporal incentives we consider the problem of providing incentives over time for an agent with constant absolute risk aversion the optimal compensation scheme is found to be a linear function of a vector of n accounts which count the number of times that each of the n kinds of observable events occurs the number n is independent of the number of time periods so the accounts may entail substantial aggregation in a continuous time version of the problem the agent controls the drift rate of a vector of accounts that is subject to frequent small random fluctuations the solution is as if the problem were the static one in which the agent controls only the mean of a multivariate normal distribution and the principal is constrained to use a linear compensation rule if the principal can observe only coarser linear aggregates such as revenues costs or profits the optimal compensation scheme is then a linear function of those aggregates the combination of exponential utility normal distributions and linear compensation schemes makes computations and comparative statics easy to do as we illustrate we interpret our linearity results as deriving in part from the richness of the agent s strategy space which makes it possible for the agent to undermine and exploit complicated nonlinear functions of the accounting aggregates

a continuous time version of the principal agent problem this paper describes a new continuous time principal agent model in which the output is a diffusion process with drift determined by the agent s unobserved effort the risk averse agent receives consumption continuously the optimal contract based on the agent s continuation value as a state variable is computed by a new method using a differential equation during employment the output path stochastically drives the agent s continuation value until it reaches a point that triggers retirement quitting replacement or promotion the paper explores how the dynamics of the agent s wages and effort as well as the optimal mix of short term and long term incentives depend on the contractual environment the understanding of dynamic incentives is central in economics how do companies motivate their workers through piece rates bonuses and promotions how is income inequality connected with productivity investment and economic growth how do financial contracts and capital structure give incentives to the managers of a corporation the methods and results of this paper provide important insights to many such questions this paper introduces a continuous time principal agent model that focuses on the dynamic properties of optimal incentive provision we identify factors that make the agent s wages increase or decrease over time we examine the degree to which current and future outcomes motivate the agent we provide conditions under which the agent eventually reaches retirement in the optimal contract we also investigate how the costs of creating incentives and the dynamic properties of the optimal contract depend on the contractual environment the agent s outside options the difficulty of replacing the agent and the opportunities for promotion our new dynamic insights are possible due to the technical advantages of continuous time methods over the traditional discrete time ones continuous time leads to a much simpler computational procedure to find the optimal contract by solving an ordinary differential equation this equation highlights the factors that determine optimal consumption and effort the dynamics of the agent s career path are naturally described by the drift and volatility of the agent s pay offs the geometry of solutions to the differential equation allows for easy comparisons to see how the agent s wages effort and incentives depend on the contractual environment finally continuous time highlights many essential features of the optimal contract including the agent s eventual retirement in our benchmark model a risk averse agent is tied to a risk neutral principal forever after employment starts the agent influences output by his continuous unobservable effort input the principal sees only the output a brownian motion with a drift that depends on the agent s effort the agent dislikes effort and enjoys consumption we assume that the agent s utility function has the income effect that is as the agent s income increases it becomes costlier to compensate him for the effort also we assume that the agent s utility of consumption is bounded from below

eoq models with general demand and holding cost functions abstract we consider the continuous deterministic infinite horizon single item inventory system within the setting of a retail sector in which the demand rate for an item is dependent on the existing inventory level the traditional parameter of the replenishment cost is kept constant but the carrying cost per unit is allowed to vary two possibilities of variation are considered a a non linear function of the length of time the item is held in inventory and b a non linear function of the amount of on hand inventory we find the optimal policies and decision rules and show that the classical eoq model is obtained as a limiting case

official central bank interventions and exchange rate volatility evidence from a regime switching analysis in this paper we investigate the effect of central bank interventions on the weekly returns and volatility of the dem usd and yen usd exchange rate returns in contrast with previous analyses we allow for regime dependent specifications and investigate whether official interventions can explain the observed volatility regime switches it is found that depending on the prevailing volatility level coordinated central bank interventions can lead to either a stabilizing or a destabilizing effect our results lead us to challenge the usual view that such interventions always imply increases in volatility c 2002 elsevier b v all rights reserved

transactions costs and nonlinear adjustment in real exchange rates an empirical investigation eolquilibrium models of real exchange rate determination in the presence of transactions costs imply a nonlinear adjustment process toward purchasing power parity ppp conventional cointegration tests which ignore the effect of transactions costs may be biased against the long run ppp hypothesis our results using both monthly data for the interwar period and annual data spanning two centuries clearly reject the linear framework in favor of an exponential smooth transition autoregressive process the systematic pattern in the estimates of the nonlinear models provides strong evidence of mean reverting behavior for ppp deviations and helps explain the mixed results of previous studies

optimal equity auctions with two dimensional types abstract we analyze the design and performance of equity auctions when bidder s valuations and opportunity costs are private information distributed according to an arbitrary joint density that can differ across bidders we identify for any incentive compatible mechanism an equivalent single dimensional representation for uncertainty we then characterize the revenue maximizing and surplus maximizing equity mechanisms and compare revenues in optimal equity and cash auctions unlike in cash auctions the adverse selection arising from bidders two dimensional types in equity auctions can lead to a global violation of the regularity condition which represents a maximal mismatch between incentive compatibility and maximization of revenue or surplus such mismatch can lead a seller to exclude bidders and demand a bidder specific stake from a non excluded bidder providing insights into when a firm should employ an auction and when it should just negotiate with a single bidder

a structural threshold model of the exchange rate under optimal intervention abstract by considering a social trade off between targeting the exchange rate and minimizing intervention costs nonlinear exchange rate dynamics can be captured by a structural threshold model this article provides a theory based empirical exchange rate model and shows how to put the model into an empirical investigation to estimate the structural threshold model we propose a two step procedure which separately estimates the permanent and temporary fundamentals of the foreign exchange market a demonstration of our approach is applied to 1981q3 2008q3 taiwan s foreign exchange market with a brief review of its monetary policies and central bank given prior estimation results are consistent with theoretical predictions and many intervention operations of taiwan s central bank are successfully identified

the roles of nominal exchange rate and relative price adjustments in ppp reversion this paper investigates the roles of the nominal exchange rate and relative prices in restoring purchasing power parity ppp by estimating their dynamics with a bivariate threshold vector error correction model our empirical results suggest a threshold cointegrating relationship between the nominal exchange rate and relative prices however these two variables play different roles in restoring ppp the nominal exchange rate adjusts to restore ppp only outside the threshold band within the band ppp is restored mainly through adjustments in relative prices

income fluctuation and asymmetric information an example of a repeated principal agent problem we examine a simple repeated principal agent model with discounting there are a risk averse borrower with an unobservable random income and a risk neutral lender the efficient contract is characterized it tends to the first best constant consumption contract as the discount factor tends to one and the time horizon extends to infinity if the time horizon is infinite and the contract is legally enforceable the borrower s utility becomes arbitrarily negative with probability one if the borrower has constant absolute risk aversion consumption is transferred between any two states at a constant interest rate which is less than the rate of time preference

on repeated moral hazard with discounting in this paper we analyze optimal contracts in an infinitely repeated agency model in which both the principal and agent discount the future we show that there is a stationary representation of the optimal contract when the agent s conditional discounted expected utility is used as a state variable this representation reduces the multi period problem to a static variational problem which can be analyzed using standard variational techniques this reduction is used to obtain several properties of the contract

understanding the empirical literature on purchasing power parity the post bretton woods era abstract this paper argues that the empirical failure of statistical tests of ppp in post bretton woods data is largely due to the low power of the tests employed this result is demonstrated using monte carlo experiments on the size and power of different testing procedures a new procedure based on horvath and watson econometric theory 11 pp 984 1014 1995 has greater power than previous approaches using the horvath watson procedure we find moderate evidence in favor of ppp in the post bretton woods era

an empirical examination of long run purchasing power parity using cointegration techniques this paper presents an empirical analysis of long run purchasing power parity ppp for five major exchange rates using recently developed econometric techniques on the cointegration of economic time series our empirical results are extremely unfavourable to the ppp hypothesis as a long run equilibrium condition even with an allowance made for measurement error and or tranportation costs in particular we are unable to reject the hypothesis of non cointegration of the exchange rate and relative prices for any of the countries concerned far from finding a stable long run proportionality between exchange rates and relative prices our results therefore suggest that they tend to drift apart without bound

when do central bank interventions influence intra daily and longer term exchange rate movements this paper examines dollar interventions by the g3 since 1989 and the reasons that trader reactions to these interventions might differ over time and across central banks market microstructure theory provides a framework for understanding the process by which sterilized central bank interventions are observed and interpreted by traders and how this process in turn might influence exchange rates using intra daily and daily exchange rate and intervention data the paper analyzes the influence of interventions on exchange rate volatility finding evidence of both within day and daily impact effects but little evidence that interventions influence longer term volatility

international currency exposures valuation effects and the global financial crisis abstract we examine the evolution of international currency exposures with a particular focus on the 2002 12 period during the run up to the global financial crisis there was a widespread shift towards positive net foreign currency positions such that relatively few countries exhibited the archetypal emerging market short foreign currency position on the eve of the global financial crisis during the crisis the upheaval in currency markets generated substantial currency generated valuation effects much of which were not reversed there is some evidence that the distribution of valuation effects was stabilizing in the sense of showing a negative covariation pattern with pre crisis net foreign asset positions