covered interest rate arbitrage in the interwar period and the keynes einzig conjecture keynes 1923 conjectured that deviations from covered interest rate parity would not be arbitraged unless a profit of at least a half of one percent on an annualized basis was available and that larger deviations would still be moderately persistent because of less than perfect elasticity of supply of arbitrage funds this two part conjecture was given further emphasis by other writers on this period notably einzig 1937 we apply nonlinear econometric techniques to a previously unexploited weekly data base for the 1920s london and new york markets and find strong support for the conjecture

structural break nonlinearity and asymmetry a re examination of ppp proposition in this study we examine the validity of the ppp proposition for 28 european countries for this purpose we propose a new unit root test procedure that allows for both gradual structural breaks a

purchasing power parity in the long run a cointegration approach this paper utilizes cointegration analysis to examine purchasing power parity relationships over a long time horizon the results indicate that the exchange rate is cointegrated strongly with the wholesale price index ratio and somewhat weakly with the consumer price index ratio the cointegrating coefficient between the exchange rate and the price ratio is close to one when cointegration is confirmed the hypothesis that the real exchange rate follows a random walk is rejected in most cases finally a new test for common trends finds no such common trends in exchange rates or price ratios copyright 1990 by ohio state university press

deviations from purchasing power parity in the long run this paper demonstrates that deviations from purchasing power parity reveal a remarkable and possibly startling consistency with martingale behavior during both fixed and flexible rate periods for a wide variety of countries and in both monthly and annual data since this pattern appears to be much more general than one would expect on the basis of models founded on international commodity arbitrage the paper proposes an alternative explanation which instead relies on financial arbitrage in bonds as the underlying mechanism this paper will demonstrate that deviations from purchasing power parity ppp reveal a remarkable and possibly startling consistency with martingale behavior during both fixed and flexible exchange rate periods for a wide variety of countries and in both monthly and annual data this pattern appears to be much more general than one would expect on the basis of models founded on international commodity arbitrage the paper therefore proposes an alternative explanation which does not presuppose free trade in goods but which instead relies on financial arbitrage in bonds as the underlying mechanism the major implication of the theory and the results is that ppp is as likely to be violated in the long as in the short run as an empirical matter deviations from ppp can be observed for most currencies at any instant see kravis et al 21 stockman 37 and genberg 15 among others these deviations are typically both cumulative and persistent the real exchange rate can remain on either side of parity for lengthy but variable time intervals of a year or more as a consequence the current consensus shared

cost allocation and convex data envelopment abstract this paper considers allocation rules first we demonstrate that costs allocated by the aumann shapley and the friedman moulin cost allocation rules are easy to determine in practice using convex envelopment of registered cost data and parametric programming second from the linear programming problems involved it becomes clear that the allocation rules technically speaking allocate the non zero value of the dual variable for a convexity constraint on to the output vector hence the allocation rules can also be used to allocate inefficiencies in non parametric efficiency measurement models such as data envelopment analysis dea the convexity constraint of the bcc model introduces a non zero slack in the objective function of the multiplier problem and we show that the cost allocation rules discussed in this paper can be used as candidates to allocate this slack value on to the input or output variables and hence enable a full allocation of the inefficiency on to the input or output variables as in the ccr model

nonlinear purchasing power parity under the gold standard 1 introductionrecent theoretical analysis of purchasing power deviations see e g dumas 1992 sercu uppal and van hull 1995 and o connell and wei 1997 demonstrates how transactions costs or the sunk costs of international arbitrage induce nonlinear adjustment of the real exchange rate to purchasing power parity ppp globally mean reverting this nonlinear process has the important property of exhibiting near unit root behavior for small deviations from ppp since small deviations from ppp are left uncorrected if they are not large enough to cover the transactions costs or the sunk costs of international arbitrage a parametric nonlinear model suggested by the theoretical literature that captures the nonlinear adjustment process in aggregate data is the exponential smooth transition autoregression model estar of ozaki 1985 a smooth rather than discrete adjustment mechanism is motivated by the theoretical analysis of dumas 1992 also as postulated by terasvirta 1994 and demonstrated theoretically by berka 2002 in aggregate data regime changes may be smooth rather than discrete given that heterogeneous agents do not act simultaneously even if they make dichotomous decisions 1 recent empirical work e g michael nobay and peel 1997 taylor peel and sarno 2001 peel and venetis 2002 has reported empirical results that suggest that the estar model provides a parsimonious fit into a variety of data sets particular for monthly data for the interwar and postwar floating period as well as for annual data spanning 200 years as reported in lothian and taylor 1996 in addition nonlinear impulse response functions derived from the estar models show that although the speed of adjustment for small shocks around equilibrium will be highly persistent larger shocks mean revert much faster than the glacial rates previously reported for linear models rogoff 1996 in this respect the estar models provide some solution to the ppp puzzle outlined in rogoff 1996 2the estar model can also provide an explanation of why ppp deviations analyzed from a linear perspective appear to be described by either a nonstationary integrated i 1 process or alternatively described by fractional processes see e g diebold husted and rush 1991 taylor peel and sarno 2001 and pippenger and goering 1993 show that the dickey fuller tests have low power against data simulated from an estar model michael nobay and peel 1997 and byers and peel 2003 show that data that is generated from an estar process can appear to exhibit the fractional property that this would be the case was an early conjecture by acosta and granger 1995 given that the estar model has a theoretical rationale whereas the fractional process is a relatively nonintuitive one the fractional property might reasonably be interpreted as a misleading linear property of ppp deviations granger and terasvirta 1999 whereas the empirical work employing estar models provides some explanation of the glacially slow adjustment speeds obtained in linear models there is one aspect of the empirical work that is worthy of further attention a second way of explaining the rogoff puzzle raised by rogoff himself 3 is to relax the assumption that the equilibrium real exchange rate is a constant see e g canzoneri cumby and diba 1996 and chinn and johnston 1996 theoretical models such as that of balassa 1964 and samuelson 1964 imply a nonconstant equilibrium in the real exchange rate if real productivity growth rates differ between countries 4 nonlinear models that incorporate proxies for these effects are found to parsimoniously fit post bretton woods data for the main real exchange rates see venetis paya and peel 2002 and paya venetis and peel 2003 naturally models that ignore this effect may generate misleading speeds of ppp adjustment to shocks in this regard the empirical results of hegwood and papell 2002 for the gold standard period are particularly interesting

some models for estimating technical and scale inefficiencies in data envelopment analysis in management contexts mathematical programming is usually used to evaluate a collection of possible alternative courses of action en route to selecting one which is best in this capacity mathematical programming serves as a planning aid to management data envelopment analysis reverses this role and employs mathematical programming to obtain ex post facto evaluations of the relative efficiency of management accomplishments however they may have been planned or executed mathematical programming is thereby extended for use as a tool for control and evaluation of past accomplishments as well as a tool to aid in planning future activities the ccr ratio form introduced by charnes cooper and rhodes as part of their data envelopment analysis approach comprehends both technical and scale inefficiencies via the optimal value of the ratio form as obtained directly from the data without requiring a priori specification of weights and or explicit delineation of assumed functional forms of relations between inputs and outputs a separation into technical and scale efficiencies is accomplished by the methods developed in this paper without altering the latter conditions for use of dea directly on observational data technical inefficiencies are identified with failures to achieve best possible output levels and or usage of excessive amounts of inputs methods for identifying and correcting the magnitudes of these inefficiencies as supplied in prior work are illustrated in the present paper a new separate variable is introduced which makes it possible to determine whether operations were conducted in regions of increasing constant or decreasing returns to scale in multiple input and multiple output situations the results are discussed and related not only to classical single output economics but also to more modern versions of economics which are identified with contestable market theories

domestic foreign interest rate differentials near unit roots and symmetric threshold models this paper investigates the near unit root behavior of interest rate differentials across countries using a symmetric band tar model that allows for a heteroscedastic error process we find that the time series properties of monthly short term interest differentials over the period 1974 2005 between the united states and canada france germany japan and the united kingdom can be characterized by a symmetric band tar process which can explain its near unit root behavior reported in the extant literature results significantly reject a linear model in favor of the alternative hypothesis of a two regime symmetric threshold model that exhibits significantly greater persistence within the threshold bands than when outside the threshold bands

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 process followed by ppp data on the properties of linearity tests recent research has reported the lack of correct size in stationarity test for ppp deviations within a linear framework however theoretically well motivated nonlinear models such as the estar appear to parsimoniously fit the ppp data and provide an explanation for the ppp puzzle employing monte carlo experiments we analyze the size and power of the nonlinear tests against a variety of nonstationary hypotheses we also fit the estar model to data from high inflation economies our results provide further support for estar specification

are real exchanges rate series really persistent evidence from three commonwealth of independent states countries this article sets out to examine the degree of persistence in the real exchange rates of kazakhstan kyrgyzstan and russia and tests the validity of purchasing power parity ppp using monthly data covering 1995 01 2013 12 period the sum of autoregressive ar coefficients is used in order to examine persistence of the real exchange rate series and grid bootstrap method is employed for the confidence intervals the tests performed suggest two results 1 covering the full sample and sub sample periods excluding kyrgyzstan in 1995 01 1998 07 and russia in 2008 09 2013 12 periods disregarding the structural breaks in the data generating process there is high persistency in real exchange rates 2 there is evidence in support of ppp covering the full sample for every country except for kyrgyzstan in 1995 01 1998 07 and russia in 2008 09 2013 12 periods

real exchange rate behavior abstract using random simulations with artificial data with identical sample characteristics to the long sample exchange rate data employed by lothian and taylor lothian j r and taylor m p 1996 the recent float from the perspective of the past two centuries journal of political economy 104 488 509 we show that standard unit root tests have extremely low power over sample sizes corresponding to the recent float the probability of rejecting the null hypothesis when it is false is extremely low with 20 years or even 50 years of data and only reaches an acceptable level over much longer spans

smooth breaks and non linear mean reversion post bretton woods real exchange rates the recent literature on purchasing power parity ppp has emphasized the role of two phenomena that may lead to the rejection of the ppp hypothesis structural breaks and non linear adjustment induced by transaction costs these two hypotheses are analyzed separately in the literature we develop tests for unit roots that account jointly for structural breaks and non linear adjustment structural breaks are modeled by means of a fourier function that allows for infrequent smooth temporary mean changes and is hence compatible with long run ppp nonlinear adjustment is modeled by means of an estar model our tests present good finite sample properties the tests are applied to a set of 15 oecd countries rers and are able to reject the null of a unit root in 14 cases the breaks are usually associated with the great appreciation and later depreciation of the dollar in the 1980s and the estar adjustment appears to play an important role

applied cost allocation the dea aumann shapley approach this paper deals with empirical computation of aumann shapley cost shares for joint production we show that if one uses a mathematical programing approach with its non parametric estimation of the cost function there may be observations in the data set for which we have multiple aumann shapley prices we suggest to overcome such problems by using lexicographic goal programing techniques moreover cost allocation based on the cost function is unable to account for differences between efficient and actual cost we suggest to employ the notion of rational inefficiency in order to supply a set of assumptions concerning firm behavior these assumptions enable us to connect inefficient with efficient production and thereby provide consistent ways of allocating the costs arising from inefficiency

tests for symmetric and asymmetric nonlinear mean reversion in real exchange rates new tests based on smooth transition autoregressive models for mean reversion in time series of real exchange rates are proposed one test forces mean reversion to be symmetric about the integrated process central case while the other permits asymmetry the tests are applied to monthly series of seventeen real exchange rates against the u s dollar and fourteen against the deutsche mark they reveal stronger evidence against the unit root null hypothesis than does the usual dickey fuller test

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

real exchange rate adjustment in european transition countries abstract in single equation tests real exchange rates show mean reversion for nine of 10 central and eastern european transition countries for the period january 1993 to december 2005 because of the shift from controlled to market economies and accompanying crises failed policy regimes and changes in exchange rate regimes unit root tests for transition countries often require allowance for structural changes accounting for structural breaks gives substantially faster mean reversion speeds than those found for major industrialized countries these fast adjustment speeds are plausible transition countries had perhaps 10 years to make unprecedented adjustments required for accession to the european union a number of papers have applied non linear models to the central and eastern european countries this paper investigates four non linear models and compares them with piece wise linear break models the break models appear superior in detecting mean reversion for the central and eastern european transition countries

the carry trade and fundamentals nothing to fear but feer itself the carry trade is the investment strategy of going long in high yield target currencies and short in low yield funding currencies recently this nave trade has seen very high returns for long periods followed by large crash losses after large depreciations of the target currencies based on low sharpe ratios and negative skew these trades could appear unattractive even when diversied across many currencies but more sophisticated conditional trading strategies exhibit more favorable payos we apply novel within economics binary outcome classication tests to show that our directional trading forecasts are informa tive and out of sample loss function analysis to examine trading performance the critical conditioning variable we argue is the fundamental equilibrium exchange rate feer expected returns are lower all else equal when the target currency is overvalued like traders researchers should incorporate this information when evaluating trading strategies when we do so some questions are resolved negative skewness is purged and market volatility vix is uncorrelated with returns other puzzles remain the more sophisticated strategy has a very high sharpe ratio suggesting market ineciency

how puzzling is the ppp puzzle an alternative half life measure of convergence to ppp summary evidence of lengthy half lives for real exchange rates in the presence of a high degree of exchange rate volatility has been considered as one of the most puzzling empirical regularities in international macroeconomics this paper suggests that the measure of half life used in the literature might be problematic and proposes alternative measures with desirable properties their focus on the cumulative effects of the shocks distinguishes them from the measures used in the literature an empirical analysis of bilateral us dollar real exchange rates employing the alternative half life measure produces results consistent with theory and indicates that the ppp puzzle is less pronounced than initially thought copyright 2012 john wiley sons ltd

purchasing power parity as a long run relation dickey fuller and stock watson tests of purchasing power parity ppp as a long run proposition are provided within the cointegration framework proposed by granger since different countries use different weights to construct price indices the traditional constraint that the coefficients on the price indices should be unity in the log linear ppp relation is relaxed the absence of a general ppp relation cannot be rejected at most a ppp relation is indicated in five out of fifteen country pairs that are examined even if a long run ppp relation exists it is not found to be useful in predicting future nominal exchange rates which is consistent with efficient speculative markets

ppp strikes back aggregation and the real exchange rate we show the importance of a dynamic aggregation bias in accounting for the ppp puzzle we prove that the aggregate real exchange rate is persistent because its components have heterogeneous dynamics established time series and panel methods fail to control for this using eurostat data we find that when heterogeneity is taken into account the estimated persistence of real exchange rates falls dramatically its half life for instance may fall to as low as eleven months significantly below the consensus view of three to five years

exchange rate pass through and inflation a nonlinear time series analysis abstract this paper investigates the relationship between the exchange rate pass through erpt and inflation by estimating a nonlinear time series model based on a simple theoretical model of erpt determination we show that the dynamics of erpt can be well approximated by a class of smooth transition autoregressive star models using the past inflation rate as a transition variable we employ several u shaped transition functions in the estimation of the time varying erpt to us domestic prices the estimation result suggests that declines in the erpt during the 1980s and 1990s are associated with lowered inflation

testing the purchasing power parity through i 2 cointegration techniques this paper contributes to the empirical literature on the purchasing power parity ppp over the post bretton woods period by providing a time series based interpretation of the controversial evidence characterizing the dynamics of real exchange rates it is shown that the persistence of deviations from the ppp between a set of european countries and the united states may be empirically attributed to the presence of i 2 stochastic trends in prices using consumer price indices interestingly the slow adjustment towards the equilibrium can be modelled through integral proportional equilibrium correction models and this evidence can be partly reconciled with theories where the inflation rate reduces the markup of profit maximizing firms acting on imperfectly competitive markets copyright 2005 john wiley sons ltd

the time series properties of norwegian inflation and nominal interest rate this article investigates the time series properties of norwegian inflation and nominal interest rate using annual data from 1850 to 2004 a number of different univariate unit root tests are employed to examine whether the time series are mean reverting or generated by unit root processes results show very strong evidence in favour of mean reversion in inflation but a unit root in the nominal interest rate this implies that there exists no long run relationship between these two variables a conclusion which is further supported by cointegration tests and estimated vector error correction models the cointegration analysis also points to an important potential pitfall when using cointegration techniques on systems where some variables are stationary processes

price regulation and relative price convergence evidence from the retail gasoline market in canada this paper explores price regulation and relative price convergence in the canadian retail gasoline market we use monthly data 2000 2010 on retail gasoline prices in 60 canadian cities to investigate i whether the retail gasoline market in canada has experienced a relative price convergence to the mean which is expected given the increased economic integration across canadian provinces and ii whether the introduction of price regulation mechanisms in new brunswick and nova scotia in july 2006 had any impact on the price convergence in these provinces we use a nonlinear panel unit root test and find solid evidence that canadian retail gasoline markets are well integrated across locales however the share of converging cities reveals a significant decline since july of 2006 the impact of price regulation on price convergence is mixed our results indicate that since the enactment of the regulation in all new brunswick cities 9 included in the dataset gasoline prices converge to the national mean volatility of price is also significantly reduced in contrast in the wake of price regulation in nova scotia all 6 cities of the province are non convergent to the mean with increased volatility and overall price level

nonlinearities in real exchange rate determination do african exchange rates follow a random walk in this article we aim at modelling the long run behaviour of the real effective exchange rates reer for a pool of african countries not much attention has been paid to this group of countries in particular to the existence of nonlinearities in the long run path of such a variable controlling for two sources of nonlinearities i e asymmetric adjustment to equilibrium and nonlinear deterministic trends allows us to gain some insight about the behaviour of the african reer we find that these sources of nonlinearities help us to explain the apparent unit root behaviour found applying linear unit root tests for most of the countries

arbitrage behaviour in the exchange rates of taiwan and japan applying the smooth transition vector error correction model with gjr garch and spillover volatility this study utilizes a smooth transition vector error correction model stvecm with glosten jagannathan runkle generalized autoregressive conditional heteroscedasticity gjr garch and spillover volatility to investigate the changes in short run return dynamics when a deviation from the comovement equilibrium between the prices of new taiwan dollar ntd and japan yen jpy exists empirical results demonstrated that both exchange rates have a nonlinear relationship with the comovement equilibrium which was captured by the logistic smooth transition vector error correction model with gjr garch and spillover volatility lstvecm gjr garch sv both exchange rates will quickly reverse to equilibrium when there are large deviations between the two exchange rates implying that information traders obtain profit in two markets and then both exchange rates continue to deviate from equilibrium when small deviations exist from comovement owing to noise trader to expand mispricing moreover small and large devi

price indices and nonlinear mean reversion of real exchange rates author affiliation jyh lin wu institute of economics national sun yat sen university kaohsiung 804 taiwan jlwu2 mail nsysu edu tw and the department of economics national chung cheng university chia yi 106 taiwan ecdjlw ccu edu tw corresponding authorpei fen chen department of international business and trade shu te university kaohsiung taiwan cpf mail stu edu tw acknowledgment we thank two anonymous referees for interesting and constructive comments on an earlier version of the paper any remaining errors are ours 1 introduction are price indices crucial for the existence of a nonlinear mean reversion of real exchange rates do prices or exchange rate adjustments dominate when deviations from purchasing power parity ppp occur is the half life implied by a nonlinear model reasonable the purpose of this article is to address the above three questions for the uk and new zealand over the period of recent float the ppp hypothesis has been one of the most intensive research issues in empirical international finance over the past two decades the rationale behind it is a simple arbitrage hypothesis which results in a linear adjustment of deviations from ppp and the stationarity of real exchange rates empirically existing evidence based on unit root tests provide mixed results for ppp abuaf and jorion 1990 mark 1990 o connell 1998a theoretically there are several reasons for the nonlinear adjustment of deviations from ppp such as the existence of market frictions or transaction costs sercu uppal and van hulle 1995 in addition models of pricing to market and exchange rate pass through give rise to impediments to goods arbitrage krugman 1987 froot and klemperer 1989 the implication is that the speed of adjustment of deviations from ppp depends on the magnitude of the deviations on the other hand the adoption of a price index is crucial in examining ppp several authors have argued that the consumer and producer price indices cpi and ppi respectively do not correspond to their theoretical counterparts and contain measurement errors and aggregation biases cheung and lai 1993 imbs et al 2005 in addition the commodity basket for cpi and ppi includes nontradable goods which impart a nonstationary component to real cpi or ppi exchange rates engel 1999 recently xu 2003 argues that the price index of traded goods tpi is the appropriate one for ppp since it reflects the behavior of arbitrage better than the cpi or ppi the purpose of this article therefore is to examine the nonlinear dynamics of tpi based real exchange rates several authors have applied a smooth transition autoregressive star model to capture the nonlinear dynamics of real exchange rates as it allows for a smooth adjustment between regimes michael nobay and peel 1997 taylor peel and sarno 2001 there are several reasons for us to apply a band threshold autoregressive tar instead of a star type model in our empirical analysis first our empirical evidence fails to reject the unit root hypothesis against the hypothesis of a nonlinear star stationary process based on the test provided by kapetanios shin and snell 2003 1 second the plots of cpi ppi and tpi based real exchange rates in figure 1 show that the tpi based real rate has the largest variation among these three real rates third our empirical evidence rejects the null hypothesis of linearity against tar type nonlinearity and supports the hypothesis that real exchange rates are tar type stationary figure 1 plots of real exchange rates for the uk and new zealand figure omitted see article image several empirical studies have applied a threshold type process to examine the nonlinear mean reversion of real exchange rates obstfeld and taylor 1997 o connell 1998b taylor 2001 sarno taylor and chowdhury 2004

dissecting the ppp puzzle the unconventional roles of nominal exchange rate and price adjustments the conventional view as expounded by sticky price models is that price adjustment determines the ppp reversion rate this study examines the mechanism by which ppp deviations are corrected nominal exchange rate adjustment not price adjustment is shown to be the key engine governing the speed of ppp convergence moreover nominal exchange rates are found to converge much more slowly than prices with the reversion being driven primarily by nominal exchange rates real exchange rates also revert at a slower rate than prices as identified by the ppp puzzle j econ lit 34 1996 647 c 2003 elsevier b v all rights reserved

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

a fractional cointegration analysis of purchasing power parity a generalized notion of cointegration called fractional cointegration is introduced to examine the long run purchasing power parity ppp hypothesis by allowing deviations from equilibrium to follow a fractionally integrated process the fractional cointegration analysis can capture a wider range of mean reversion behavior than standard cointegration analyses this gain is flexibility in modeling subtle mean reverting dynamics is found to be important for a proper evaluation of long run ppp empirical results based on historical data for the 1914 1989 period show that ppp reversion exists and can be characterized by a fractionally integrated process in three out of five countries studied the results support ppp as a long run phenomenon though significant short run deviations from ppp can exist

nonparametric analysis of technical and allocative efficiencies in production in this paper we extend varian s 1984 nonparametric production analysis to situations when the set of observed output input and price data is not consistent with profit maximization for at least one firm in such cases varian s results imply that no production possibility set containing all observations can rationalize the observed data we identify each firm whose performance given the prices faced by it may be found consistent with profit maximization relative to some production possibility set containing all observed output input vectors we show that the set 4 of all such firms can itself be weaklv rationalized in the sense that there exists a closed convex and monotone production possibility set that contains all the observations and relative to which the performance of all the firms in the set 8o is consistent with profit maximization given their respective prices by definition firms not included in this largest set d of efficient observations unambiguously deviate from profit maximizing behavior for any production possibility set containing all observations we follow farrell 1957 and analyze these deviations into technical and allocative efficiency measures considering as admissible all closed convex and monotone production possibility sets relative to which the performance of each firm in the set g remains consistent with profit maximization we then describe nonparametric methods for determining the tightest upper and lower bounds on the technical allocative and aggregate efficiency measures evaluated relative to all such admissible production possibility sets it is seen that the tightest upper bound on the technical efficiency measure is the same as the value computed by the nonparametric efficiency evaluation technique known as data envelopment analysis thus establishing a link between this literature in management science operations research and the nonparametric production analysis in economics

long run purchasing power parity in the 1920s abstract this paper presents an empirical analysis of long run purchasing power parity ppp during the 1920s float using recently developed methodology on the cointegration of economic time series our results are generally supportive of ppp as a long run equilibrium condition on which exchange rates tended to converge over the period for dollar sterling however there is some evidence of a non stationary drift away from fundamentals during the last year or so before britain s return to the gold standard perhaps due to speculation our results also appear to reconcile some apparently conflicting evidence in the literature

temporal aggregation and purchasing power parity persistence this paper uses a unique new monthly us uk real exchange rate series for the january 1794 december 2009 period to reexamine the academic debate over purchasing power parity ppp the consensus view described by rogoff 1996 is that ppp holds in the long run but short run deviations are very persistent with half lives ranging from 3 to 5 years most of the literature using long time series relies on the annual data developed by lee 1976 and lothian and taylor 1996 which were both constructed from underlying higher frequency data sources estimates of purchasing power parity persistence using these series may therefore be subject to temporal aggregation bias we find evidence of aggregation bias which indicates the half life of ppp deviations has been overestimated in much of the previous literature we also find that estimates of the half lives are further reduced once we account for the harrod 1933 balassa 1964 samuelson 1964 effect the result of aggregation bias appears to be robust even when considering the case that real exchange rates exhibit nonlinear dynamics

a bias aggregation theorem abstract in a market where some traders are rational maximize expected utility and others are systematically biased deviate from expected utility due to some bias parameter do equilibrium prices necessarily depend on focusing on the case where there is an aggregate and systematic bias in the population we show that market prices can still be unbiased hence we establish that systematically biased agents do not necessarily imply biased market prices

validity of purchasing power parity for selected latin american countries linear and non linear unit root tests abstract the aim of this study is to examine empirically the validity of ppp in the context of unit root tests based on linear and non linear models of the real effective exchange rate of argentina brazil chile colombia mexico peru and venezuela for this purpose we apply the harvey et al 2008 linearity test and the non linear unit root test kruse 2011 the results show that the series with linear characteristics are argentina brazil chile colombia and peru and those with non linear characteristics are mexico and venezuela the linear unit root tests indicate that the real effective exchange rate is stationary for chile and peru and the non linear unit root tests evidence that mexico is stationary in the period analyzed the results show support for the validity of ppp in only three of the seven countries

allocating fixed costs and resources via data envelopment analysis abstract in this paper we show that data envelopment analysis dea can be viewed as maximising the average efficiency of the decision making units dmus in an organisation building upon this we present dea based models for a allocating fixed costs to dmus and b allocating input resources to dmus simultaneous to allocating input resources output targets are also decided for each dmu numeric results are presented for a number of example problems taken from the literature

characterizing an equitable allocation of shared costs a dea approach abstract in many applications to which dea could be applied there is often a fixed or common cost which is imposed on all decision making units this would be the case for example for branches of a bank which can be accessed via the numerous automatic teller machines scattered throughout the country a problem arises as to how this cost can be assigned in an equitable way to the various dmus in this paper we propose a dea approach to obtain this cost allocation which is based on two principles invariance and pareto minimality it is shown that the proposed method is a natural extension of the simple one dimensional problem to the general multiple input multiple output case

causes of nonlinearities in low order models of the real exchange rate abstract this paper investigates the extent to which modern dsge models which feature local currency pricing home bias nontraded goods and incomplete markets can generate nonlinear real exchange rate dynamics that are consistent with those found in the time series literature using data from the current floating period our key findings are as follows first if the true model can be appropriately characterized as a set of linear equations then linearity tests that utilize univariate autoregressions of the real exchange rate suffer from an omitted variables problem which leads them to overestimate the true incidence of nonlinearity consequently studies that fail to control for this problem may spuriously find evidence of nonlinearities in the data despite the fact that the data generating process may be linear second we propose a strategy that can largely eliminate this distortion finally we find that dsge models solved using higher order approximations are capable of generating true structural nonlinearities in real exchange rates both asymptotically and in short samples

three methods to share joint costs or surplus abstract we study cost sharing methods with variable demands of heterogeneous goods additive in the cost function and meeting the dummy axiom we consider four axioms scale invariance si demand monotonicity dm upper bound for homogeneous goods ubh placing a natural cap on cost shares when goods are homogeneous average cost pricing for homogeneous goods acph the random order values based on stand alone costs are characterized by si and dm serial costsharing by dm and ub the aumann shapley pricing method by si and acph no other combination of the four axioms is compatible with additivity and dummy journal of economic literature classification numbers c71 d62 d63

threshold cointegration and purchasing power parity in the pacific nations the paper uses a threshold cointegration methodology to explore the properties of long run purchasing power parity ppp in the pacific nations using japan and the usa as base countries it is shown that long run ppp holds for most asian countries but that the adjustment mechanism is asymmetric in contrast to symmetric error correction models it is found that asymmetric adjustments of nominal exchange rates play an important role in eliminating deviations from long run ppp

measuring the persistence of deviations from purchasing power parity with a fractionally integrated star model abstract empirically elements of both fractional long memory and threshold non linearity are present in the real exchange rates of the g 7 countries against the us notably in the eu countries estimated half lives of deviations from ppp using median unbiased corrections to conventional linear autoregressive models corroborate existing evidence related to the ppp paradox as half lives range from at least four years to an infinite number of years in contrast for each eu country accounting for threshold non linearity results in estimated half lives that can be less than three years even with the allowance for fractional long memory

smooth transition models and arbitrage consistency slow adjustment of real exchange rate towards equilibrium in linear models has long puzzled researchers stimulating the adoption of nonlinear models the exponential smooth transition model has been particularly successful providing faster adjustment speeds this paper discusses some of its theoretical limitations for example that expectations are adaptive we propose a new nonlinear model conceptually superior to the estar model since it is consistent with rational expectations one of its advantages is that it can be solved and estimated by nonlinear least squares using monthly post 1973 real exchange rate data we show that the model implies even faster speeds of adjustment

the effects of small sample bias in threshold autoregressive models abstract this paper investigates threshold autoregressive tar models that contain a limited number of observations in some regimes simulations show that within the context of the real exchange rate literature parameter estimates exhibit significant small sample bias even with long time series data these distortions create substantial power losses in attempting to identify values of coefficients from data

three regime asymmetric star modeling and exchange rate reversion the breakdown of the bretton woods system and the adoption of generalized floating exchange rates ushered in a new era of exchange rate volatility and uncertainty this increased volatility leads economists to search for economic models able to describe observed exchange rate behavior in the present paper we propose more general star transition functions that encompass both threshold nonlinearity and asymmetric effects our framework allows for a gradual adjustment from one regime to another and considers threshold effects by encompassing other existing models such as tar models we apply our methodology to three different exchange rate data sets one for developing countries and official nominal exchange rates the second for emerging market economies using black market exchange rates and the third for oecd economies

understanding post euro law of one price deviations we put together a unique panel of thousands of good level prices before and after the euro to compare the determinants and understand the evolution of goods price dispersion across europe over time we find that tradeability and nontraded inputs play a significantly smaller role for cross country price dispersion after the adoption of the euro and for eurozone economies as compared to european union ones we then compare the distributions of law of one price lop deviations over time to understand how the degree of integration across european economies changed after the euro our tests reveal that the distributions after the euro are typically significantly different from those before consistent with a greater degree of integration utilizing our unique panel data set to trace the location of individual goods in the distribution of lop deviations we ask how the price advantage or disadvantage evident in these price distributions evolves over time and whether goods characteristics play a role for the persistence of these lop deviations lop deviations for these goods are highly correlated over 5 or 10 year horizons and correlations remain significantly high over longer horizons these correlations are greater for homogeneous as compared to differentiated goods and vary across countries finally for most of these european economies and goods price advantage is typically revealed to be more persistent than price disadvantage

searching for nonlinearities in real exchange rates a recent innovation in modeling exchange rates has been the use of nonlinear techniques such as threshold autoregressive models and its smooth transition variants this paper investigates the smooth transition autoregressive star modeling strategy in an application to real exchange rates the key findings are as follows first using the methodology advocated by terasvirta 1994 we find evidence of nonlinear dynamics for several of the spot dollar real exchange rates using monthly data on five of the g7 countries however once estimated we find that the star specification is appropriate for only one of the three exchange rate series indicated to be an estar process moreover using simulations we show that the underlying methodology used to detect nonlinearities in the data exhibit substantial size biases which we attribute to influential observations we also investigate an alternative nonlinear specification and find that we can model the dollar sterling and the dollar lira real exchange rates better as an open loop tar process instead of a setar process

dynamic hedge ratio for stock index futures application of threshold vecm this study represents one of the first papers in stock index futures arbitrage literature to investigate the effects of arbitrage threshold on stock index futures hedging effectiveness by using threshold vector error correction model hereafter threshold vecm moreover in contrast to prior studies focusing on examining case studies involving mature stock markets this study not only adopts us s p 500 stock market as the sample but also adds an analysis of one emerging stock market hungarian bsi and examines the differences between them finally this investigation employs a rolling estimation process to examine the impact of arbitrage threshold behaviours on the setting of futures hedging ratio the empirical findings of this study are consistent with the following notions first arbitrage behaviour reduces co movement between futures and spot markets and increases the volatility of both futures and spot markets second this article denotes the outer regime of futures spot market for the case of hung

choice under uncertainty with the best and worst in mind neo additive capacities the concept of a non extreme outcome additive capacity neo additive capacity is introduced neo additive capacities model optimistic and pessimistic attitudes towards uncertainty as observed in many experimental studies moreover neo additive capacities can be applied easily in economic problems as we demonstrate by examples this paper provides an axiomatisation of choquet expected utility with neo capacities in a framework of purely subjective uncertainty

central bank intervention exchange rate regime and the purchasing power parity motivated by the argument that central bank intervention leads to non linear exchange rate adjustment processes we examine purchase power parity ppp by applying quantile unit root tests to the exchange rates of the new taiwan dollar ntd vis a vis seven asian currencies we show that exchange rate regime matters in determining whether ppp holds while ppp holds overwhelmingly during the period when the ntd is under the fixed exchange rate regime it is present only for some exchange rates during the managed floating rate regime for exchange rates exhibiting mean reversion the reversion occurs mainly when the shocks are large in contrast to conclusion in the literature our test results show little evidence of asymmetric mean reversion between positive and negative shocks

revisiting the uncertain unit root in gdp and cpi testing for non linear trend reversion we test for the presence of a unit root in u s gdp and cpi allowing for non linear trend reversion under the alternative hypothesis in contrast to most previous results we find evidence in favour of trend stationarity for both variables

the purchasing power parity debate originally propounded by the 16th century scholars of the university of salamanca the concept of purchasing power parity ppp was revived in the interwar period in the context of the debate concerning the appropriate level at which to re establish international exchange rate parities broadly accepted as a long run equilibrium condition in the post war period it first was advocated as a short run equilibrium by many international economists in the first few years following the breakdown of the bretton woods system in the early 1970s and then increasingly came under attack on both theoretical and empirical grounds from the late 1970s to the mid 1990s accordingly over the last three decades a large literature has built up that examines how much the data deviated from theory and the fruits of this research have provided a deeper understanding of how well ppp applies in both the short run and the long run since the mid 1990s larger datasets and nonlinear econometric methods in particular have improved estimation as deviations narrowed between real exchange rates and ppp so did the gap narrow between theory and data and some degree of confidence in long run ppp began to emerge again in this respect the idea of long run ppp now enjoys perhaps its strongest support in more than 30 years a distinct reversion in economic thought

noisy information distance and law of one price dynamics across us cities abstract us micro price data at the city level suggests that both the volatility and the persistence of law of one price deviations are rising in the distance between us cities a standard two city equilibrium model with trade costs can predict the relationship between volatility and distance but not between persistence and distance we show that if there is imperfect information about the state of nominal aggregate demand with noisy signals that are asymmetric across cities then distance and persistence will be positively correlated our main results are shown to be robust to the introduction of sticky prices and multiple cities

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

the effects of railroad development on price convergence among the states of the usa from 1866 to 1906 this study examines the effects of the reduced transaction costs on the price behaviours in the second half of the nineteenth century where declines in transaction costs were mainly caused by railroad development during this period it employs a panel test introduced by levin and lin 1992 on the convergence of wheat and corn prices using a panel of 48 us states from 1866 to 1906 the results show that by decreasing transportation costs railroads played an important role in price convergence among states of the usa for wheat and corn during the postbellum period

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

a century of purchasing power parity confirmed the role of nonlinearity abstract taylor 2002 claims that purchasing power parity ppp has held over the 20th century based on strong evidence of stationary for century long real exchange rates for 20 countries lopez et al 2005 however found much weaker evidence of ppp with alternative lag selection methods we reevaluate taylor s claim by implementing a recently developed nonlinear unit root test by park and shintani 2005 we find strong evidence of nonlinear mean reversion in real exchange rates that confirms taylor s claim we also find a possible misspecification problem in using the estar model that may not be detected with taylor approximation based tests

do prediction markets produce well calibrated probability forecasts this article presents new theoretical and empirical evidence on the forecasting ability of prediction markets we develop a model that predicts that the time until expiration of a prediction market should negatively affect the accuracy of prices as a forecasting tool in the direction of a favourite longshot bias that is high likelihood events are underpriced and low likelihood events are over priced we confirm this result using a large data set of prediction market transaction prices prediction markets are reasonably well calibrated when time to expiration is relatively short but prices are significantly biased for events farther in the future when time value of money is considered the miscalibration can be exploited to earn excess returns only when the trader has a relatively low discount rate

testing long run purchasing power parity under exchange rate targeting abstract the present paper exploits the idea that empirical estimates of the long run ppp relationship may compound two distinct influences coming from the behavior of market participants and policy makers when the latter are targeting the exchange rate this tends to bias tests of long run ppp against its acceptance the validity of the theoretical arguments is assessed by drawing on the experience of two european union countries greece and france for the post bretton woods period estimation biases due to the omission of policy effects are found to be significant only in the case of greece for france our test results provide evidence bearing on the effectiveness of the competitive disinflation strategy pursued by the french authorities