An improved novelty criterion for resource allocating networks

Online model order complexity estimation remains one of the key problems in neural network research. The problem is further exacerbated in situations where the underlying system generator is non-stationary. In this paper, we introduce a novelty criterion for resource allocating networks (RANs) which is capable of being applied to both stationary and slowly varying non-stationary problems. The deficiencies of existing novelty criteria are discussed and the relative performances are demonstrated on two real-world problems : electricity load forecasting and exchange rate prediction.

Forecasting exchange rates with linear and nonlinear models

In this paper, the exchange rate forecasting performance of neural network models are evaluated against the random walk, autoregressive moving average and generalised autoregressive conditional heteroskedasticity models. There are no guidelines available that can be used to choose the parameters of neural network models and therefore, the parameters are chosen according to what the researcher considers to be the best. Such an approach, however,implies that the risk of making bad decisions is extremely high, which could explain why in many studies, neural network models do not consistently perform better than their time series counterparts. In this paper, through extensive experimentation, the level of subjectivity in building neural network models is considerably reduced and therefore giving them a better chance of Forecasting exchange rates with linear and nonlinear models 415 performing well. The results show that in general, neural network models perform better than the traditionally used time series models in forecasting exchange rates.

Volatility changes in drachma exchange rates

In January 2001 Greece joined the eurozone. The aim of this article is to examine whether an intention to join the eurozone had any impact on exchange rate volatility. We apply the Iterated Cumulative Sum of Squares (ICSS) algorithm of Inclan and Tiao (1994) to a set of Greek drachma exchange rate changes. We find evidence to suggest that the unconditional volatility of the drachma exchange rate against the dollar, British pound, yen, German mark and ECU/Euro was nonstationary, exhibiting a large number of volatility changes prior to European Monetary Union (EMU) membership. We then use a news archive service to identify the events that might have caused exchange rate volatility to shift. We find that devaluation of the drachma increased exchange rate volatility but ERM membership and a commitment to joining the eurozone led to lower volatility. Our findings therefore suggest that a strong commitment to join the eurozone may be sufficient to reduce some exchange rate volatility which has implications for countries intending to join the eurozone in the future.

Forecasting exchange rates with linear and nonlinear models

In this paper the exchange rate forecasting performance of neural network models are evaluated against random walk and a range of time series models. There are no guidelines available that can be used to choose the parameters of neural network models and therefore the parameters are chosen according to what the researcher considers to be the best. Such an approach, however, implies that the risk of making bad decisions is extremely high which could explain why in many studies neural network models do not consistently perform better than their time series counterparts. In this paper through extensive experimentation the level of subjectivity in building neural network models is considerably reduced and therefore giving them a better chance of performing well. Our results show that in general neural network models perform better than traditionally used time series models in forecasting exchange rates.

The microstructure of the foreign exchange market:the determinants of bid-ask spreads in the foreign exchange market

The purpose of this thesis is to shed more light in the FX market microstructure by examining the determinants of bid-ask spread for three currencies pairs, the US dollar/Japanese yen, the British pound/US dollar and the Euro/US dollar in different time zones. I examine the commonality in liquidity with the elaboration of FX market microstructure variables in financial centres across the world (New York, London, Tokyo) based on the quotes of three exchange rate currency pairs over a ten-year period. I use GARCH (1,1) specifications, ICSS algorithm, and vector autoregression analysis to examine the effect of trading activity, exchange rate volatility and inventory holding costs on both quoted and relative spreads. ICSS algorithm results show that intraday spread series are much less volatile compared to the intraday exchange rate series as the number of change points obtained from ICSS algorithm is considerably lower. GARCH (1,1) estimation results of daily and intraday bid-ask spreads, show that the explanatory variables work better when I use higher frequency data (intraday results) however, their explanatory power is significantly lower compared to the results based on the daily sample. This suggests that although daily spreads and intraday spreads have some common determinants there are other factors that determine the behaviour of spreads at high frequencies. VAR results show that there are some differences in the behaviour of the variables at high frequencies compared to the results from the daily sample. A shock in the number of quote revisions has more effect on the spread when short term trading intervals are considered (intra-day) compared to its own shocks. When longer trading intervals are considered (daily) then the shocks in the spread have more effect on the future spread. In other words, trading activity is more informative about the future spread when intra-day trading is considered while past spread is more informative about the future spread when daily trading is considered

Bid-ask spread dynamics in foreign exchange markets

The aim of this paper is to examine the short term dynamics of foreign exchange rate spreads. Using a vector autoregressive model (VAR) we show that most of the variation in the spread comes from the long run dependencies between past and future spreads rather than being caused by changes in inventory, adverse selection, cost of carry or order processing costs. We apply the Integrated Cumulative Sum of Squares (ICSS) algorithm of Inclan and Tiao (1994) to discover how often spread volatility changes. We find that spread volatility shifts are relatively uncommon and shifts in one currency spread tend not to spillover to other currency spreads. © 2013.

Kelet-közép-európai devizaárfolyamok előrejelzése határidős árfolyamok segítségével (Forecasting the exchange rates of three Central-Eastern European currencies with forward exchange rates)

Írásunkban azt vizsgáljuk, hogy a hosszú lejáratú határidős árfolyamok stacionaritását feltételező hibakorrekciós modellek, amelyeknek korábbi számítások szerint - a világ devizapiaci forgalmának mintegy 75 százalékát kitevő fejlett ipari országokra alkalmazva - kitűnő a mintán kívüli előrejelző erejük, hogyan képesek három keletközép- európai ország devizaárfolyamát előrejelezni. A három vizsgálat alá vont deviza (cseh, magyar, lengyel) esetében az eredmények relációnként nagyon eltérnek, és összességében kedvezőtlenebbek, mint a fejlett ipari országokra kapott eredmények, amit a nem teljesen rugalmas árfolyamrezsim, a rendelkezésre álló adatsor rövidsége, az eurózóna-csatlakozáshoz kapcsolódó bizonytalanságok, a devizakockázati és a határidős kamatprémium létezése, továbbá a Balassa-Samuelson-hatás együttes befolyásaként tudunk értelmezni. JEL kód: E43, F31, F47. /===/ This paper studies whether models that assume long-maturity forward exchange rates are stationary (which proved in earlier studies to provide superior forecasting ability when applied to exchange rates of major currencies) are capable of forecasting the Euro exchange rates of three Central-East European currencies (the Czech koruna, Hungarian forint and Polish zloty). The results for the three currencies differ from each other and are generally much worse than those obtained earlier for major currencies. These unfavourable results are attributed to the consequences of managed exchange-rate systems, to the short time series available, to uncertainties related to future Euro-zone entry, to the existence of a foreign exchange and term premium, and to the Balassa–Samuelson effect.

Megmenthető-e az euróövezet? (Can the eurozone be saved?)

Az euró válságának szélesebb globális összefüggései vannak, mind a kiváltó okait, mind a nemzetközi pénzügyi rendszer működésének hiányosságait illetően. Az európai monetáris integráció szilárd reálgazdasági alapokon nyugszik. Az euró teljesítménye mind az árstabilitás, mind az árfolyamok ingadozása tekintetében megfelelőnek tekinthető. Az euróválság szuverénadósság-válság, és leginkább a zóna egyes (déli) országait érinti. Az euróválság okai többrétűek: ezek között az eurózóna hibás konstrukcióját, téves koncepcionális feltételezéseit, a politikai kompromisszumokkal folyamatosan megnyomorított működését említhetjük leginkább. A közös pénz önmagában nem oka a válságnak és nem is bűvös ellenszer. A hibás gazdaságpolitikáért belül ugyanúgy bűnhődni kell, mint kívül. Görögország, vagy Írország elsősorban nem azért került válságba, mert tagjai az eurózónának, hanem mert hibás gazdaságpolitikát folytattak. Nem zárható ki az eurózóna szétesése, de kicsi az esélye. / === / The euro crisis has broad global connections, both in terms of deficiencies of the international monetary system, and of the crisis of the global financial markets. The European monetary integration is based on strong real-economic foundations. The performance of the euro has been satisfactory both in terms of price and exchange rate stability. The present crisis is a sovereign debt crisis, and it is concentrated mainly on some Southern members. The causes of the crisis are manifold: wrong institutional and policy structures, mistaken conceptual assumptions, and the distortion of its operation by continuous political compromises. The contradictions between common monetary policy and the national fiscal policies, the failure of disciplining role of the markets, the weakness of control of national fiscal policies, the dangers of "one size fits all" monetary policy, the failure of finding the proper national policy mixes, particularly in terms of income and structural policies, and the underestimation of social and cultural differences, can be particularly stressed. The common monetary policy failed to secure the necessary equilibrium among liquidity, stability and growth. Greece and Ireland got in crisis not because they are members of the euro zone, but because of their mistaken economic policies. The collapse of the euro zone cannot be excluded, but the chances of it are limited.

Kiigazítás recesszió nélkül. Esettanulmány a magyar stabilizációról = Adjustment without recession: A Case Study of Hungarian Stabilization

1995. március 12-én a magyar kormány és a központi bank szigorú kiigazítási és stabilizációs programot hirdetett meg. A cikk az első eredmények számbavételére tesz kísérletet. A program meghirdetése előtt Magyarország két egymást követő év- ben hatalmas fizetésimérleg-hiányt mutatott fel, és nemzetközi megítélése romlani kezdett. A program radikális intézkedései nyomán elkerülhetővé vált a mexikói vál- sághoz hasonló pénzügyi katasztrófa. Sok makrogazdasági mutató jól érzékelhető javulást jelez: lényegesen csökkent a kereskedelmi mérleg és a folyó fizetési mérleg hiánya, a költségvetés elsődleges egyenlege pozitív lett. Az ilyesféle stabilizációs programokat rendszerint súlyos visszaesés és a munkanélküliség nagy növekedése kíséri. Magyarország elkerülte ezeket a mellékhatásokat: a GDP drasztikus vissza- esés helyett valamelyest tovább növekedett, és a munkanélküliség változatlan ma- radt. A javulásnak nagy ára volt: az életszínvonal erőteljes csökkenése, az infláció felgyorsulása, bár a magyarországi infláció még mindig a kézben tartott, mérsékelt infláció sávjában maradt. A cikk ismerteti a program heterodox módszereit: 1. nagy leértékelés, az előre meghirdetett csúszó árfolyam rezsimjének bevezetése, valamint ideiglenes import- vámpótlék kivetése; 2. határozott jövedelempolitika, amely 12 százalékos reálbércsök- kenést kényszerített ki; 3. fiskális intézkedések, köztük jóléti jogosultságok csök- kentése (a program meghirdetése előtt ezek a jogosultságok tabuk voltak); 4. a hitel- kínálat átcsoportosítása a vállalati szektor javára, a jövedelmezőség növekedése; 5. feszített (bár nem mértéktelenül feszített) monetáris politika, amely lehetővé tette a sikeres vállalatok expanzióját; 6. a privatizáció felgyorsítása, nagy és sikeres lépé- sek egyes kulcsszektorok (energia, telekommunikáció) privatizációjában. Végezetül a tanulmány óva int a túlzott magabiztosságtól és felhívja a figyelmet a potenciális veszélyekre. A makrogazdasági javulás még törékeny. A magyar fejlődés legbiztatóbb sajátossága a termelékenység erőteljes és folyamatos növekedése. / === / On March 12, 1995 Hungary s government and central bank announced a tough program of adjustment and stabilization. This study is an attempt to asses the first results. Before the announcement of the program Hungary had a huge current account deficit for two consecutive years, and her international reputation started to decline. The program s radical measures made it possible to avoid a Mexico-style financial catastrophe. Many macroeconomic indicators show tangible improvement: the trade deficit and the deficit on the current account have been reduced significantly, the primary budget shifted to surplus. These kinds of adjustment programs are usually associated with deep recession and a large increase of unemployment. Hungary avoided these adverse side-effects: GDP instead of a drastic decline, continued to grow somewhat, and unemployment remained unchanged. There was a high price for the improvement: a sharp decline in the standard of living, and an acceleration of inflation, although Hungary is still in the range of controlled, moderate inflation. The paper describes the heterodox instruments of the program: (1) large devaluation, followed by a new exchange rate regime of pre-announced crawling peg, and a temporary import surcharge, (2) energetic income policy, enforcing a 12% cut in real wages; (3) fiscal measures, including cuts in welfare entitlements. That happened for the first time: before the program entitlements had been regarded as taboo ; (4) reallocation of credit supply in favor of the enterprise sector; increase of profitability; (5) tight (but not excessively tight) monetary policy, allowing the expansion of successful private busi- ness; (6) acceleration of privatisation, including large and successful steps in the privatisation of some key sectors (energy, telecommunication). Finally the paper warns against excessive self- confidence and draws the attention to potential dangers. The macroeconomic improvement is still fragile. The most reassuring feature of Hungary s development is the impressive and persistent improvement of productivity.

Kamatlábak és árszint kis, nyitott gazdaságban = Interest rates and price levels in a small open economy

A tanulmány azt vizsgálja, hogy a különböző kamatlábaknak milyen hatásai vannak az árszintre, illetve a nominális árakra egy nyitott elsősorban kis, nyitott gazdaságban szabad tőkeáramlás mellett. Míg a zárt gazdaságban csupán a nominális és reálkamatláb megkülönböztetése a lényeges, nyitott gazdaságban a kamatlábak vizsgálatakor meg kell fontolnunk a kamatlábparitás kérdését is. Tisztáznunk kell a reálkamatláb összetevőit, amelyben fontos szerepet kap mind az árfolyam-begyűrűzés (pass-through), mind pedig a kockázati prémium mértéke. A kamatlábhatások vizsgálatakor először azt a mechanizmust elemezzük, amely által a kamatláb befolyásolja a tartós jószágok költségét (explicit vagy implicit bérleti díját). Másodszor az exportszektor termelési döntése és a hazai kamatláb viszonyára vonatkozó mechanizmust vizsgáljuk. Belátjuk, hogy az exportáló szektor döntései függetlenek lehetnek a belföldi kamatlábaktól. Harmadszor bizonyos árazási viselkedéseket tanulmányozunk. Bebizonyítjuk, hogy a kamatláb olyan növelése, ami nem változtat a jelenlegi árfolyamon, árszintnövelő az importőr ország számára. Megfogalmazható az a nézet, hogy ha van is a kamatlábaknak keresleti hatása a zárt gazdaságban, a kis, nyitott gazdaságban ez vélhetőleg sokkal gyengébb. _____ The study examines what effects various interest rates have on the price level and nomi-nal prices in an open (primarily small) economy with free flows of capital. A closed economy calls for a distinction only between nominal and real rates of interest, but in an open economy, questions of interest-rate parity have to be considered as well. It is nec-essary to clarify the factors behind the real interest rate important for price-level pass-through and for the scale of risk premium. Analysis of interest-rate effects begins with the mechanism whereby the interest rate influences the cost of fixed assets (explicit or implicit rents). Secondly, the mechanism behind the relation of export-sector production decisions and domestic interest rates is examined. It emerges that decisions of the export sector are independent of domestic interest rates. Thirdly, certain types of pricing behav-iour are studied. It is shown that a rise in the interest rate that does not alter the present exchange rate is a price-raising factor for the importing country. It can be assumed that if the interest rate has a demand effect in a closed economy, this will presumably be much weaker in a small open economy.

A dinâmica da taxa de câmbio no Brasil face às operações swap (2002-2015)

This dissertation investigates, based on the Post-Keynesian theory and on its concept of monetary economy of production, the exchange rate behavior of the Brazilian Real in the presence of Brazilian Central Bank's interventions by means of the so-called swap transactions over 2002-2015. Initially, the work analyzes the essential properties of an open monetary economy of production and, thereafter, it presents the basic propositions of the Post-Keynesian view on the exchange rate determination, highlighting the properties of foreign exchange markets and the peculiarities of the Brazilian position into the international monetary and financial system. The research, thereby, accounts for the various segments of the Brazilian foreign exchange market. To accomplish its purpose, we first do a literature review of the Post-Keynesian literature about the topic. Then, we undertake empirical exams of the exchange rate determination using two statistical methods. On the one hand, to measure the volatility of exchange rate, we estimate Auto-regressive Conditional Heteroscedastic (ARCH) and Generalized Auto-regressive Conditional Heteroscedastic (GARCH) models. On the other hand, to measure the variance of the exchange rate in relation to real, financial variables, and the swaps, we estimate a Vector Auto-regression (VAR) model. Both experiments are performed for the nominal and real effective exchange rates. The results show that the swaps respond to exchange rate movements, trying to offset its volatility. This reveals that the exchange rate is, at least in a certain magnitude, sensitive to swaps transactions conducted by the Central Bank. In addition, another empirical result is that the real effective exchange rate responds more to the swaps auctions than the nominal rate.

International Capital Flows and Monetary Policy Spillovers

This dissertation examines the drivers and implications of international capital flows. The overarching motivation is the observation that countries not at the centre of global financial markets are subject to considerable spillovers from centre countries, notably from their monetary policy. I present new empirical evidence on the determinants of the observed patterns of international capital flows and monetary policy spillovers, and study their effect on both financial markets and the real economy. In Chapter 2 I provide evidence on the determinants of a puzzling negative correlation observed between productivity growth and net capital inflows to developing and emerging market economies (EMEs) since 1980. By disaggregating net capital inflows into their gross components, I show that this negative correlation is explained by capital outflows related to purchases of very liquid assets from the fastest growing countries. My results suggest a desire for international portfolio diversification in liquid assets by fast growing countries is driving much of the original puzzle. In the reminder of my dissertation I pivot to study the foreign characteristics that drive international capital flows and monetary policy spillovers, with a particular focus on the role of unconventional monetary policy in the United States (U.S.). In Chapter 3 I show that a significant portion of the heterogeneity in EMEs' asset price adjustment following the quantitative easing operations by the Federal Reserve (the Fed) during 2008-2014 can be explained by the degree of bilateral capital market frictions between these countries and the U.S. This is true even after accounting for capital controls, exchange rate regimes, and domestic monetary policies. Chapter 4, co-authored with Michal Ksawery Popiel, studies unconventional monetary policy in a small open economy, looking specifically at the case of Canada since the global financial crisis. We quantify the effect Canadian unconventional monetary policy shocks had on the real economy, while carefully controlling for and quantifying spillovers from U.S. unconventional monetary policy. Our results indicate that the Bank of Canada's unconventional monetary policy increased Canadian output significantly from 2009-2010, but that spillovers from the Fed's policy were even more important for increasing Canadian output after 2008.

Devaluation, competitiveness and new business formation in emerging countries

In September 2010, Brazil’s Finance Minister, Guido Mantega, used the term “currency war” with reference to monetary policies implemented by different countries to generate an artificial devaluation of their currency and achieve a cheaper, more competitive domestic economy that may be attractive to foreign investors. Similar cases have been documented since the 1930s Great Depression, when several countries abandoned the gold standard as backing for their currencies. More recently, a large-scale asset purchase by Japan’s Central Bank in 2013 was singled out as a strategy aimed at generating devaluation of the yen. This research uses statistics of new business formation density reported by Doing Business for 30 emerging countries in the period 2004-2011 to evaluate the impact of devaluation measured by the behavior of the real effective exchange rate (REER) on the rate of new business formation (NBF). It is determined how variables associated with competitiveness affect the relationship between devaluation and business formation. Results show that devaluation has a positive effect on NBF in the short term, which gets diluted in the long term. Countries with greater competitiveness have less dependence on devaluation to increase the number of businesses.

Forecasting exchange rates in the presence of instabilities

Many exchange rate papers articulate the view that instabilities constitute a major impediment to exchange rate predictability. In this thesis we implement Bayesian and other techniques to account for such instabilities, and examine some of the main obstacles to exchange rate models' predictive ability. We first consider in Chapter 2 a time-varying parameter model in which fluctuations in exchange rates are related to short-term nominal interest rates ensuing from monetary policy rules, such as Taylor rules. Unlike the existing exchange rate studies, the parameters of our Taylor rules are allowed to change over time, in light of the widespread evidence of shifts in fundamentals - for example in the aftermath of the Global Financial Crisis. Focusing on quarterly data frequency from the crisis, we detect forecast improvements upon a random walk (RW) benchmark for at least half, and for as many as seven out of 10, of the currencies considered. Results are stronger when we allow the time-varying parameters of the Taylor rules to differ between countries. In Chapter 3 we look closely at the role of time-variation in parameters and other sources of uncertainty in hindering exchange rate models' predictive power. We apply a Bayesian setup that incorporates the notion that the relevant set of exchange rate determinants and their corresponding coefficients, change over time. Using statistical and economic measures of performance, we first find that predictive models which allow for sudden, rather than smooth, changes in the coefficients yield significant forecast improvements and economic gains at horizons beyond 1-month. At shorter horizons, however, our methods fail to forecast better than the RW. And we identify uncertainty in coefficients' estimation and uncertainty about the precise degree of coefficients variability to incorporate in the models, as the main factors obstructing predictive ability. Chapter 4 focus on the problem of the time-varying predictive ability of economic fundamentals for exchange rates. It uses bootstrap-based methods to uncover the time-specific conditioning information for predicting fluctuations in exchange rates. Employing several metrics for statistical and economic evaluation of forecasting performance, we find that our approach based on pre-selecting and validating fundamentals across bootstrap replications generates more accurate forecasts than the RW. The approach, known as bumping, robustly reveals parsimonious models with out-of-sample predictive power at 1-month horizon; and outperforms alternative methods, including Bayesian, bagging, and standard forecast combinations. Chapter 5 exploits the predictive content of daily commodity prices for monthly commodity-currency exchange rates. It builds on the idea that the effect of daily commodity price fluctuations on commodity currencies is short-lived, and therefore harder to pin down at low frequencies. Using MIxed DAta Sampling (MIDAS) models, and Bayesian estimation methods to account for time-variation in predictive ability, the chapter demonstrates the usefulness of suitably exploiting such short-lived effects in improving exchange rate forecasts. It further shows that the usual low-frequency predictors, such as money supplies and interest rates differentials, typically receive little support from the data at monthly frequency, whereas MIDAS models featuring daily commodity prices are highly likely. The chapter also introduces the random walk Metropolis-Hastings technique as a new tool to estimate MIDAS regressions.

Predicción de volatilidad de la rentabilidad diaria del mercado del azúcar y su aplicación en la razón de cobertura

Este trabajo predice la volatilidad de la rentabilidad diaria del precio del azúcar, en el período compren­dido entre 1 de junio de 2011 y el 24 de octubre de 2013. Los datos diarios utilizados fueron los precios del azúcar, del etanol y la tasa de cambio de la moneda de Brasil (Real) en dólares. Se usaron modelos multivariados de volatilidad autoregresiva condicional generalizada. A partir de la predicción de los precios del azúcar se calcula la razón de cobertura de mínima varianza. Los resultados muestran, que la razón de cobertura es 0.37, esto significa que, si un productor adverso al riesgo, que tiene la intención de eliminar un porcentaje de la volatilidad de la rentabilidad diaria del mercado mundial del azúcar, y espera vender 25 contratos de azúcar, cada uno de ellos de 50,84 toneladas (1.271 toneladas), el número de contratos optimo tomando cobertura a futuro será 9 y el número de contratos sin tomar cobertura (de contado) será 16.