do the foreign exchange rates really follow a random walk an empirical question revisited abstract the random walk behavior of nominal exchange rates using daily weekly and monthly data and of real exchange rates using monthly data is investigated for seven major currencies and fails to be confirmed but fails less frequently for the post 1979 period

mean reversion in real exchange rates evidence and implications for forecasting abstract the stationarity of real exchange rates over the recent flexible exchange rate period is an issue that has long bedeviled researchers in international finance using a constrained multivariate framework this paper provides the strongest evidence yet that real exchange rates were mean reverting over the 1973 93 period we also investigate shifts in long run real exchange rates which may be important for the purpose of forecasting out of sample forecasting shows that the random walk model is outperformed by a mean stationary model especially at long horizons in addition there are substantial forecasting benefits from using a multivariate approach

forecasting foreign exchange rates with an intrinsically nonlinear dynamic speed of adjustment model forecasting foreign exchange rates is an important but difficult process therefore it is important to use a superior forecasting model the paper takes up this criterion and proposes to describe and forecast foreign exchange rates by developing an intrinsically nonlinear model with variable and dynamic speeds of adjustment it is found that the speed of adjusting the random or expected to the equilibrium rate is very slow implying that fiscal policy statistically insignificat and monetary policy statistically significant may be ineffective to induce changes in the adjustment speed we also find that the nonlinear dynamic model improves forecasting performance implying that nonlinearities in the sense of functional forms are exploitable for improved point forecasting of foreign exchange rates

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

national price levels purchasing power parity and cointegration a test of four high inflation economies abstract the time series properties of exchange rates and wholesale prices from four high inflation countries show some evidence in support of purchasing power parity tests for stationarity of real exchange rates and cointegration among price and exchange rate variables are presented for argentina brazil chile and israel during the 1970s and 1980s error correction models describe the mechanism of adjustment to long run equilibrium

sources of real exchange rate fluctuations empirical evidence from four pacific basin countries in international finance the competing hypothesis that the logarithms of real exchange rates appear to be well described as random walks during a period of floating rate has found some support studies by adler and lehmann 2 hakkio 12 and mark 18 are examples of work supporting this view if a real exchange rate process has been approximated to be non stationary it implies there is little tendency for the real exchange rate to be mean reverting and also that deviations from the purchasing power parity ppp are permanent modern models of exchange rate determination suggest that real shocks can induce permanent changes in the real exchange rate stockman 21 pointed out that according to the equilibrium approach the behavior of real exchange rates since the collapse of bretton woods could reflect not the importance of sluggish price level adjustment but rather the influence of real shocks with significant permanent components moreover the evidence in campbell and clarida 5 and huizinga 13 suggests that real exchange rates contain both permanent and transitory components with most of their variation explained by the permanent components however recent studies employing long run data or more powerful tests tend to confirm the ppp hypothesis studies by abuaf and jorion 1 kim 16 whitt 22 and diebold husted and rush 7 are four such examples their evidence shows that real exchange rates are stationary which implies that the behavior of real exchange rates are influenced by transitory nominal disturbances hence the validity of ppp remains at issue identifying the sources of exchange rate fluctuations is important not only for establishing the validity of ppp but also for achieving successful exchange rate stabilization attempts to stabilize exchange rate changes that are due to economic fundamentals could be futile and even harmful to the economy in addition measuring the relative importance of permanent and transitory shocks on exchange rates is essential for exchange rate modeling if exchange rates are dominated by real shocks then the equilibrium approach offered by stockman 21 is appropriate in analyzing the behavior of exchange rates conversely if the evidence suggests the contrary then the disequilibrium approach of dornbusch 8 should be considered as an alternative as a consequence

consumer biases and mutual ownership abstract we show how ownership of the firm by its customers as well as nonprofit status can prevent firms from using contractual terms that take advantage of consumer biases by eliminating an outside residual claimant with control over the firm these alternatives to investor ownership reduce the incentive of the firm to offer such terms however customers who are unaware of their behavioral biases may fail to recognize this advantage of non investor owned firms we present evidence from the consumer financial services market that supports our theory comparing contract terms we find that mutually owned firms offer lower penalties such as default interest rates and higher up front prices such as introductory interest rates than do investor owned firms however consumers most vulnerable to these penalties are no more likely to use mutually owned firms

purchasing power parity and unit root tests using panel data abstract this paper reports the results of unit root tests for real exchange rates using a panel framework this panel approach provides greatly improved power compared to conventional univariate time series unit root tests we obtain evidence supporting ppp over the recent flexible exchange rate period for g 6 and oecd countries we show explicitly that failure to find such evidence in previous research was due to the low power of the tests

an empirical examination of long run purchasing power parity as theory of international commodity arbitrage an empirical analysis of long run purchasing power parity ppp as a theory of international commodity arbitrage between uk and us prices and the sterling us dollar exchange rate for the period 1975 1980 is presented econometric techniques concerning the cointegration of economic time series are applied to a sample of 35 manufactured commodities which in 1977 constituted approximately a quarter of the net output of all manufacturing industry in great britain our results are extremely unfavourable to the ppp hypothesis as a stable long run proportionality between exchange rates and disaggregated prices

the foreign exchange market a random walk with a dragging anchor this paper explores some anomalies in the foreign exchange market it is hard to find evidence of either short term overshooting or of longer term reversion to an equilibrium the forward exchange rate contains virtually no information on future spot rates discussions with practitioners indicate that longer term speculation based on fundamentals is strictly limited and survey data and other evidence suggest that expectations and speculation are based on a variety of models the interplay between speculation based on fundamentals and on a random walk or chartist approach influences the outcome this endorses the prior model of j a frankel and k a froot copyright 1988 by the london school of economics and political science

antitrust issues in schumpeterian industries a half century ago joseph schumpeter 1950 chapters 5 8 presented a vision of modern capitalism in which monopolies are common but frequently swept aside by a perennial gale of creative destruction p 84 this gale is driven not by price competition but by competition from the new commodity the new technology competition which strikes not at the margins of the profits of the existing firms but at their foundations and their very lives p 84 i focus here on the personal computer pc software hereafter simply software industry which resembles this vision i discuss some important issues this industry poses for antitrust policy and in the final section illustrate with examples from the microsoft case

political vs currency premia in international real interest differentials a study of forward rates for 24 countries abstract different approaches to quantifying the degree of capital mobility for a cross section of currencies particularly saving investment correlations and tests of real interest parity have appeared to show a surprisingly low degree of financial integration we use a new data set forward rate data for 24 countries including many small industrialized countries and seven ldcs to decompose the real interest differential into two parts the covered interest differential or political premium and the real forward discount or currency premium the latter in turn can be decomposed into the exchange risk premium and expected real depreciation we find a high degree of capital mobility across political boundaries for most of the g 11 countries plus hong kong and singapore for our sample period of 1982 to 1987 even for most of the other ldcs and smaller industrialized countries for which covered interest parity clearly fails the political premium is not as big a component of the real interest differential as the currency premium france would appear to have higher capital mobility than most by the criterion of real interest differentials but is seen in fact to have low capital mobility by the criterion of covered interest differentials a clear example of the superiority of the latter criterion

does the exchange rate follow a random walk a monte carlo study of four tests for a random walk abstract several authors have urged that real and nominal exchange rates follow a random walk conditions under which the exchange rate follows a random walk are reviewed in this paper many of these do not appear to hold therefore the empirical evidence presents a puzzle some evidence suggets the exchange rate follows a random walk while other evidence suggests the opposite should be true this paper attempts to reconcile the evidence it is argued that the tests for a random walk have low power monte carlo evidence on four tests for a random walk is presented that suppors this claim

relative ppp in the medium run abstract this paper tests the relative purchasing power parity rppp hypothesis on month by month post 1972 data and still obtains regression coefficients that are close to unity two methodological aspects have contributed to this encouraging result firstly although all rppp tests are vis a vis the usa we nevertheless exploit our a priori knowledge about the implications of these usd based equations on ppp relations between cross rates so in a sense we use all information implicit in all cross rates too secondly we selected an instrumental variable that is specifically designed to cope with lead and lag effects in non traded vs traded goods inflation our estimates indicate that most lead and lag effects seem to occur within a six month window jel f31

market efficiency and cointegration an application to the sterling and deutschemark exchange markets abstract the assumption that the foreign exchange market is efficient that is that agents are risk neutral and use all available information rationally so that the forward exchange rate is an unbiased predictor of the future spot rate is a property often imposed in theoretical international macroeconomic models although a vast empirical literature has evolved to test market efficiency we use recent developments in the theory of cointegration to provide new methods of testing several aspects of foreign exchange market efficiency we ffind evidence inconsistent with market efficiency for both germany and the united kingdom

interest rates inflation and taxes the foreign connection abstract in this note it is shown that the existence of taxes on nominal interest receipts in an international setting introduces a non neutrality in that a change in expected inflation in one country must change at least one expected real interest rate or the path of the real exchange rate

the real interest rate a multi country empirical study how real interest rates behave over time is critical to our understanding of many macroeconomic issues and much recent research has pursued this question very little of the research however has focused on real interest rates outside the united states this paper is an empirical exploration of real interest rate movements in seven oecd countries from 1967 ii to 1979 ii further research is needed on real rates in other countries for several reasons not only are measures of foreign real rates of interest in their ownright but extending an analysis of real rates to other countries also has the following additional benefits it can generate more powerful statistical tests of propositions previously tested on u s data and yield information on whether results found for the u s hold up in other countries this study pursues several questions that have arisen naturally from this earlier work is the hypothesis that the real rate is constant rejected when the analysis is extended to other countries does the real rate decline with increased inflation and money growth in other countries besides the united states how reliable is the fisher effect in which nominal interestrates reflect changes in expected inflation are movements in nominal interest rates a reliable indicator of movements in real rates what kind of variationsin real interest rates are there in different countries have real rates declined from the 60s to the 70s for other countries besides the u s this abstract was borrowed from another version of this item

flexible exchange rates prices and the role of news lessons from the 1970s recent experience with flexible exchange rate systems has led to renewed interest in the operation of foreign exchange markets as reflected in many recent studies of the principal determinants of exchange rates the 1970s witnessed the dramatic alteration of the international monetary system from a regime of pegged exchange rates which prevailed for about a quarter of a century since the bretton woods conference into a regime of flexible though managed rates as a consequence of the emergence of the new legal and economic system traders national governments and international organisations were confronted with new economic problems choices and instruments during the 1970s ex change rates fluctuated widely and inflation rates accelerated the international monetary system had to accommodate extraordinarily large oil related shocks which affected trade flows in goods and assets huge oil payments had to be recycled uncertainties concerning future developments in international politics reached new heights and the prospects for the world economy got gloomier these developments placed unprecedented pressures on the markets for foreign exchange as well as on other asset markets they were associated with a large slide in the value of the us dollar and resulted in speeding up the creation of new institutions like the european monetary system which provided the formal framework for the management of exchange rates among members

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

exchange rate volatility international trade and the value of exporting firms abstract increased exchange rate volatility positively affects the value of exporting firms via the price and volume impacts of exchange rates and also makes an exporting strategy more attractive relative to the direct investment investment in export production capacity could therefore be a positive function of exchange rate volatility firms would also be more willing to sustain losses i e to engage in dumping before they abandon their export markets the effect on the volume and value of trade is ambiguous

persistence in foreign exchange rates abstract this study examines the long run behavior of seven daily nominal exchange rates using univariate and multivariate persistence measures our results indicate that for some currencies the long run behavior deviates from that of a pure random walk in certain periods the multivariate estimates reflect the effect of both the ems exchange rate mechanism and increased post louvre accord coordinated intervention a large portion of the effect of a shock in one currency on another currency s long run value can be attributed to contemporaneous effects on the other currencies

mean reversion in real exchange rates a modified dickey fuller test which is approximately uniformly most power invariant is employed to examine mean reversion in real exchange rates results from this test provide a wider and more significant support for mean reversion than the standard dickey fuller test

cointegration tests of purchasing power parity in africa abstract despite two decades of implementing economic reforms there is still a significant gap between official and black market exchange rates in africa african policy makers continue to implement exchange rate policies based largely on the assumption that purchasing power parity ppp holds this paper examines whether there is empirical support for ppp in africa we used johansen s cointegration technique and error correction modeling on annual data for black market exchange rates and cpi in 30 countries covering 1960 97 we found strong support for the ppp doctrine as a useful guide for exchange rate policy reform in africa

on unit roots and real exchange rates empirical evidence and monte carlo analysis this paper presents some empirical evidence that real exchange rate series contain a unit root in their time series respresentation which cancels out on first differencing using the augmented dickey fuller test the power of this test is also tested using monte carlo methods and it is found to be quite powerful against a range of stationary local alternatives the findings imply the absence of any tendency of the nominal exchange rate to converge on purchasing power parity even in the long run