the income and terms of trade effects a permanent versus transitory decomposition in us trade abstract this paper develops an empirical analysis of the us trade balance with particular attention to the distinction between permanent and transitory disturbances to income and the terms of trade arising from real monetary and demand supply shocks the results indicate that the income effects on the trade balance differ remarkably depending on whether a given change is permanent or transitory for instance a permanent increase in income deteriorates the trade balance whereas a transitory increase improves it the results are contrasted to the predictions of the mundell fleming dornbusch model and intertemporal models jel f32

when do long run identifying restrictions give reliable results many recent articles have identified behavioral disturbances in vector autoregressions by imposing restrictions on the long run effects of shocks this article demonstrates that this approach will be unreliable unless the underlying economy satisfies three types of strong restrictions although many aspects of these issues have been raised before this article draws out and illustrates the implications for inferences under the long run scheme furthermore it provides strategies for dealing with the problems

optimal hedge ratio under a subjective re weighting of the original measure abstractin this article we study a risk minimizing hedge ratio with futures contracts where the risk of the hedged portfolio is measured through a spectral risk measure srm thus incorporating the degree of agent s risk aversion we empirically estimate the optimal hedge ratio ohr using a long time series of uk and us equity indices the eurusd and eurgbp exchange rates and four liquid commodities brent crude oil corn gold and copper to represent different asset classes comparing the results with common ohrs such as the minimum variance and the minimum expected shortfall we find that the agent s risk aversion has a material impact and should not be ignored in risk management

capital flows and gdp in emerging economies and the role of global spillovers abstract this paper provides a global analysis of capital flow impacts on gdp for selected emerging economies as additional control variables we also include currency reserves and effective exchange rates in our analysis we distinguish between gross and net capital flows and also assess the impact of both fdi and portfolio flows accounting for the fact that common factors have been the main drivers of capital flows while country specific determinants pull factors drive the response to such shocks we analyze shocks to country groups but consider country specific responses based on a bayesian time varying panel var framework in the spirit of canova and ciccarelli 2009 based on a sample of 24 economies our results show a robust positive effect of capital flows on gdp except for korea both gross and net capital flows display a positive impact for around two quarters the impact of effective exchange rates on gdp hardly offers an explanation for a possible transmission of capital flow effects with effective depreciations both positively and negatively linked to gdp we also find that the effect of net portfolio flows is even more positive compared to net fdi flows for emerging economies finally we provide evidence that the importance of global factors increases in times of crises

the effect of asymmetries on optimal hedge ratios there is widespread evidence that the volatility of stock returns displays an asymmetric response to good and bad news this article considers the impact of asymmetry on time varying hedges for financial futures an asymmetric model that allows forecasts of cash and futures return volatility to respond differently to positive and negative return innovations gives superior in sample hedging performance however the simpler symmetric model is not inferior in a hold out sample a method for evaluating the models in a modern risk management framework is presented highlighting the importance of allowing optimal hedge ratios to be both time varying and asymmetric

causes of capital flows in developing countries abstract this paper investigates the causes of capital flows in four developing countries mexico chile korea and malaysia using structural decomposition analysis it finds that the recent resurgence in capital movements is largely due to external reasons such as decreases in the world interest rate or recession in industrial countries domestic factors including country specific productivity shocks and demand shocks are relatively less important another interesting finding is that the fundamental causes of capital flows differ little across the countries under study these results suggest that developing countries need to pay attention to the financial arrangements associated with capital flows and to exchange rate policy as well as macroeconomic fundamentals to avoid financial crises in a world of increased capital mobility

marketing margins and price uncertainty the case of the u s wheat market this paper seeks to determine the effect of changes in output price risk on marketing margins a theoretical model of price determination in a marketing channel with risk averse firms is developed this model shows that if marketing firms are competitive and decreasingly absolute risk averse then an increase in output price risk should result in higher expected marketing margins empirical evidence from the wheat marketing channel supports the theoretical model increased price variability significantly increases wheat marketing margins for both the farm mill margin and the mill retail margin these results suggest a potential benefit from price stabilization programs

bivariate garch estimation of the optimal commodity futures hedge six different commodities are examined using daily data over two futures contract periods cash and futures prices for all six commodities are found to be well described as martingales with near integrated garch innovations bivariate garch models of cash and futures prices are estimated for the same six commodities the optimal hedge ratio ohr is then calculated as a ratio of the conditional covariance between cash and futures to the conditional variance of futures the estimated ohrs reveal that the standard assumption of a time invariant ohr is inappropriate for each commodity the estimated ohr path appears non stationary which has important implications for hedging strategies

what is the major determinant of cross border banking flows abstract this study examines the major determinant of cross border credit flows through global banks across 70 countries employing a bayesian dynamic latent factor model we decompose volatilities of banking flows into the contribution of a global common factor regional common factor and country specific factor the results indicate that the global and regional common factor explains about 40 50 percent of volatility in overall cross border banking flows in particular the contribution of the global common factor increased in the 2000s simultaneously main determinants are largely heterogeneous across countries this implies that the desirable policy response to credit inflows may differ for each host country

a bivariate markov regime switching garch approach to estimate time varying minimum variance hedge ratios this article develops a new bivariate markov regime switching bekk generalized autoregressive conditional heteroscedasticity garch rs bekk garch model the model is a state dependent bivariate bekk garch model and an extension of gray s univariate generalized regime switching grs model to the bivariate case to solve the path dependency problem inherent in the bivariate regime switching bekk garch model we propose a recombining method for the covariance term in the conditional variance covariance matrix the model is applied to estimate time varying minimum variance hedge ratios for corn and nickel spot and futures prices out of sample point estimates of hedging portfolio variance show that compared to the state independent bekk garch model the rs bekk garch model improves out of sample hedging effectiveness for both corn and nickel data we perform white s 2000 data snooping reality check to test for predictive superiority of rs bekk garch over the benchmark model and find that the difference

the optimal value at risk hedging strategy under bivariate regime switching arch framework unlike the majority of other hedging literatures in which variance is taken as the risk indicator this article uses the value at risk var as the risk management tool of the hedged portfolio this article adopts a bivariate markov regime switching autoregressive conditional heteroscedastic swarch model to formulate the optimal var hedging strategy and then compares it with the other dynamic futures hedging strategies mentioned in the literature in hedging performance using taiwan stock exchange capitalization weighted stock index taiex futures data the in sample and out of sample results shows that when var is used as the criterion to measure the futures hedging effectiveness the performance of the dynamic hedging strategy is superior to that of the static hedging strategy and the performance of the optimal var hedging strategy is better than that of the minimum variance and mean variance hedging strategies besides from the standpoint that the volatility of hedge ratio and hedged portfolio var

estimating the effects of global patent protection in pharmaceuticals a case study of quinolones in india under the trips agreement wto members are required to enforce product patents for pharmaceuticals the debate about the merits of this requirement has been extremely contentious many low income economies claim that patent protection for pharmaceuticals will result in substantially higher prices for medicines with adverse consequences for the health and well being of their citizens on the other hand research based global pharmaceutical companies argue that prices are unlikely to rise significantly because most patented products have therapeutic substitutes in this paper we empirically investigate the basis of these claims central to the ongoing debate is the structure of demand for pharmaceuticals in poor economies where because health insurance coverage is so rare almost all medical expense are met out of pocket using a detailed product level data set from india we estimate key price and expenditure elasticities and supply side parameters for the fluoroquinolones sub segment of the systemic anti bacterials i e antibiotics segment of the indian pharmaceuticals market we then use these estimates to carry out counterfactual simulations of what prices profits and consumer welfare would have been had the fluoroquinolone molecules we study been under patent in india as they were in the u s at the time our results suggest that concerns about the potential adverse welfare effects of trips may have some basis we estimate that in the absence of any price regulation or compulsory licensing the total annual welfare losses to the indian economy from the withdrawal of the four domestic product groups in the fluoroquinolone sub segment would be on the order of u s 450 million or about 73 of the sales of the entire systemic anti bacterials segment in 2000 of this amount foregone profits of domestic producers constitute roughly 50 million or 11 the overwhelming portion of the total welfare loss therefore derives from the loss of consumer welfare in contrast the profit gains to foreign producers in the absence of any price regulation are estimated to be only around 53 million per year

the impact of exchange rate volatility on international trade reduced form estimates using the garch in mean model abstract in this paper we use a multivariate garch in mean model of the reduced form of multilateral exports to examine the relationship between nominal exchange rate volatility and export flows and prices the model imposes rationality on perceived exchange rate volatility unlike conventional two step strategies tests are performed for five industrialized countries over the post bretton woods era we find that the garch conditional variance has a statistically significant impact on the reduced form equations for all countries for most of the countries the magnitude of the effect is stronger for export prices than quantities in addition the estimated magnitude of the impact of volatility on exports is not robust to using the conventional estimation strategy jel f41 f31

risk response in the beef marketing channel a multivariate generalized arch m approach a model of the farm retail price spread for beef is specified under rational expectations in which systematic risk response on the part of marketing intermediaries is allowed the three equation structural model contains potentially time varying risk terms in margin and supply equations which i approximate and estimate using a multivariate garch in mean approach the estimated model is used to infer relative risk premia in beef margins and to simulate short run equilibrium risk effects results indicate that price risk has at times had substantial impacts on farm and retail beef prices and production

the role of transportation costs in the economics of commodity markets transportation costs still play an important role in the economics of commodity markets in this paper i present a theoretical framework aimed at describing spatial arbitrage under uncertainty i analyze the effect of changing transport costs on different yet related variables volume of trade volatility of prices and levels of spatial price differentials as a tribute to enke and samuelson the model is referred to as the stochastic enke samuelson model it provides predictions for variables such as price volatilities or correlations which cannot be defined in the deterministic framework of the standard spatial price equilibrium model the statistical tests display a convergent array of evidence in favor of the model

hedging multiple price uncertainty in international grain trade commodity and freight futures contracts are analyzed for their effectiveness in reducing uncertainty for international traders a theoretical model is developed for a trader exposed to several types of risk ols hedge ratio estimation is compared to the sur and the multivariate garch methodologies explicit modeling of the time variation in hedge ratios via the multivariate garch methodology using all derivatives and taking into account dependencies between prices results in reductions in risk even after accounting for transaction costs results confirm that while the commodity futures contracts are important for hedging risk freight futures are a useful mechanism for reducing risk copyright 2000 oxford university press

marketing costs and instability in the international grain trade fixed factors in the international grain marketing system reduce flexibility and make adjustment to variable trade volumes difficult a theoretical model is used to show how this causes marketing costs with trade instability to exceed those occurring under stability also it is demonstrated that the marketing system increases the adverse effects of price variation on importers and exporters supporting empirical evidence primarily dealing with ocean shipping is presented the results suggest that stable trade volumes may reduce marketing costs significantly thus the marketing system should be considered in questions dealing with instability in the international grain trade

crack spread hedging accounting for time varying volatility spillovers in the energy futures markets crude oil heating oil and unleaded gasoline futures contracts are simultaneously analysed for their effectiveness in reducing price volatility for an energy trader a conceptual model is developed for a trader hedging the crack spread various hedge ratio estimation techniques are compared to a multivariate garch model that directly incorporates the time to maturity effect often found in futures markets modelling of the time variation in hedge ratios via the multivariate garch methodology and thus taking into account volatility spillovers between markets is shown to result in significant reductions in uncertainty even while accounting for trading costs copyright 2002 john wiley sons ltd

the dynamic effects of aggregate demand and supply disturbances we interpret fluctuations in gnp and unemployment as due to two types of disturbances disturbances that have a permanent effect on output and disturbances that do not we interpret the first as supply disturbances the second as demand disturbances demand disturbances have a hump shaped mirror image effect on output and unemployment the effect of supply disturbances on output increases steadily over time peaking after two years and reaching a plateau after five years

market volatility and the dynamic hedging of multi commodity price risk commodity cash and futures prices experienced a severe boom and bust cycle between 2006 and 2009 increases in commodity price volatility have raised concerns about the usefulness of commodity futures and options as risk management tools dynamic hedging strategies have the potential to improve risk management when conditional co variances depart significantly from their unconditional long run counterparts and may be useful to decision makers despite their greater complexity and higher transaction costs we propose a nonparametric copula based generalized autoregressive conditional heteroscedastic npc garch approach to estimate time varying hedge ratios and evaluate the benefits of dynamic hedging during four sub periods between 2000 and 2011 using a stylized texas cattle feedlot management problem the npc garch approach allows for a flexible nonlinear and asymmetric dependence structure between cash and futures prices for different commodities we find that npc garch dynamic hedging performs bette

risk behavior and rational expectations in the u s broiler market this study examines the empirical implications of extending the rational expectations hypothesis reh to include price uncertainty a general estimation framework that incorporates both the restrictions on structural parameters and the variance covariance terms is developed garch time series processes are used to generate time varying expectations of both the means and the variances of exogenous variables the empirical application is with a quarterly model of the u s broiler industry the results indicate that the rational expectation of price variance is an important determinant of broiler supply a formal test indicates that the restrictions implied by the reh cannot be rejected

a copula garch approach for analyzing dynamic conditional dependency structure between liquefied petroleum gas freight rate product price arbitrage and crude oil price abstract global liquefied petroleum gas lpg trade shows an increasing trend but is under researched this paper focuses on the lpg market and aims to model the dependence dynamics among lpg freight rates crude oil price and propane location arbitrage conditional copula garch model is applied to estimate dependencies different types of copulas with both time invariant and time varying dependence structures are fitted and their suitability has been compared the findings suggest that firstly baltic lpg blpg freight rate and the arbitrage between propane far east and middle east prices have conditional time varying dependence and the dependence is higher in market downturns furthermore blpg and the arbitrage between far east and us propane prices have symmetric dependence and such a relationship has strengthened since 2013 secondly middle east propane price is found to have the strongest correlation with crude oil prices compared to far east and us propane prices indicating higher sensitivity to crude oil price changes last but not least the relationship between crude oil and blpg is relatively weak and mostly positive

income effects on the trade balance this paper investigates the income effects on the trade balance with particular attention to the distinction between permanent and transitory disturbances for the united states japan germany and the united kingdom in all four countries movements in the trade balance have mostly been associated with transitory changes in income the latter also are negatively associated with the trade balance in marked contrast permanent changes in income have little to do with the trade balance these results are examined in light of intertemporal models and real business cycle models copyright 1996 by mit press

international evidence on the historical properties of business cycles we contrast properties of real quantities with those of price levels and stocks of money for ten countries over the last century although the magnitude of output fluctuations has varied across countries and periods relations among real quantities have been remarkably uniform properties of price levels however exhibit striking differences between periods inflation rates are more persistent after world war ii than before and price level fluctuations are typically procyclical before world war ii and countercyclical afterward fluctuations in money are less highly correlated with output in the postwar period but are no more persistent than in earlier periods jel e32 e31

mutual funds flows and the geography of contagion abstract this paper studies the dynamics and geography of investments made by international mutual funds located in advanced markets i identify precise global and regional dynamics in equity and bond flows very few countries receive or lose funding in isolation i also find strong evidence of global contagion when financial conditions in developed markets change emerging markets funding is heavily affected i illustrate this finding by deriving contagion maps showing where contagion spreads and with what intensity in general the results suggest that push effects from advanced market investors affect massively developing countries and expose them to sudden stops and surges

european natural gas seasonal effects on futures hedging abstract this paper is the first to discuss the design of futures hedging strategies in european natural gas markets nbp ttf and zeebrugge a common feature of energy prices is that conditional mean and volatility are driven by seasonal trends due to weather demand and storage level seasonalities this paper follows and extends the ederington and salas 2008 framework and considers seasonalities in mean and volatility when minimum variance hedge ratios are computed our results show that hedging effectiveness is much higher when the seasonal pattern in spot price changes is approximated with lagged values of the basis futures price minus spot price this fact remains true for short a week and long one three and six months hedging periods furthermore volatility of weekly price changes also has a seasonal pattern and is higher in winter than in summer a simple volatility seasonal model that is based on sinusoidal functions on the basis improves the risk reduction obtained by strategies in which hedging ratios are estimated with linear regressions seasonal hedging strategies linear regression based strategies or even a naive position perform better than more sophisticated statistical methods

international real business cycles we ask whether a two country real business cycle model can account simultaneously for domestic and international aspects of business cycles with this question in mind we document a number of discrepancies between theory and data the most striking discrepancy concerns the correlations of consumption and output across countries in the data outputs are generally more highly correlated across countries than consumptions in the model we see the opposite

exact consumer s surplus and deadweight loss consumer s surplus is a widely used tool in applied welfare economics both economic theorists and cost benefit analysis often use consumer s surplus despite its somewhat dubious reputation the basic idea is to evaluate the value to a consumer or his willingness to pay for a change in price of a good from say pricep to pricep because price changes affect consumer welfare an evaluation of this effect is often a key input to public policy decisions yet consumer s surplus is probably the most controversial of widely used economic concepts both paul samuelson and ian little conclude that the economics profession would be better off without it it is my feeling of the situation that substantial agreement exists on the correct quantities to be measured the amount the consumer would pay or would need to be paid to be just as well off after the price change as he was before the price change the quantities correspond to john hicks compensating variation measures an alternative measure which takes ex post price change utility as the basis of comparison is hicks equivalent variation the controversy arises in the measurement of these quantities the usual measurement procedure is to use the area to the left of the marshallian market demand curve between two price levels jules dupuit originated this measure of welfare change and alfred marshall and hicks derived appropriate conditions for its use the primary condition for the area to the left of the demand curve to correspond to the compensating variation is to have constant marginal utility of income marshall gave this condition and if it holds the same quantity will be derived as the area to the left of the compensated hicksian demand curve this area to the left of the compensated demand curve is exactly what the compensating variation and equivalent variation measure thus the constant marginal utility of income is a sufficient condition for marshallian consumer s surplus to be equal to hicks consumer s surplus in this case arnold harberger s plea to use the welfare triangle as one half times the product of the price change times the quantity change to measure deadweight loss corresponds to the correct theoretical amount of welfare change in a recent paper robert willig derives bounds for the percentage difference between the correct measure of either the compensating or equivalent variation and the marshallian measure derived form the market demand curve his bounds which depend on the income elasticity of demand for the single good in the region of price change being considered as well as the proportion of the consumer s income spent on the good demonstrate that the marshallian consumer s surplus is often a good approximation to hicks consumer s surplus the fact that the proportion of the consumer s income spent matters as well as the income elasticity was first pointed out by harold hotelling willig contends that the approximation error will be less than the errors involved in estimating the demand curve thus he hopes to remove the need for apology that applied economists often need to give to theorists who remark on the inappropriateness of using marshallian consumer s surplus to measure welfare change however in this paper i show that for the case primarily considered by willig of a single price change which is also the situation in which consumer s surplus is often used in applied work no approximation is necessary professor of economics massachusetts institute of technology and research associate national bureau of economic research i would like to thank peter diamond erwin diewert daniel mcfadden robert merton robert solow hal varian joel yellin and the referees for help and comments research support from the national science foundation is acknowledged the reason that we still have two rather than one of samuelson s six measures of consumer s surplus arises from an index number problem of the correct basis for the welfare comparison i will give both measures but plan to concentrate on the compensating variation

strategic pricing of new pharmaceuticals this paper provides empirical evidence on the leading factors affecting the prices of new pharmaceuticals both at introduction and after 4 6 and 8 years most important is the extent of therapeutic advance embodied in a new product for drugs which represent important therapeutic gains launch prices can be two or three times those of existing drugs used for the same purposes while drugs that largely duplicate the actions of currently available products are typically priced at comparable levels in addition the number of branded substitutes has a substantial negative effect on launch prices which reflects the importance of competitive pressures duplicate products thereby play an important economic role in pharmaceutical markets

estimates of the demand for ethical pharmaceutical drugs across countries and time the aggregate demand for ethical pharmaceutical drugs using country level data for seven countries pooled across an eight year period is estimated the regression analysis reveals that the net price paid by consumers has a negative effect on the average number of prescriptions per capita while income has a positive effect moreover the parameter estimates suggest thst the demand is relatively elastic in most countries and that the income elasticity is greater than one

pharmaceutical patents prices and welfare losses policy options for india under the wto trips agreement c oncerns on the effect of product patents on the prices of medicines have been acute in many developing countries which up to the entry into force of the world trade organisation wto agreement on trade related aspects of intellectual property rights trips in 1995 could and did disallow such patenting in their national patent laws with trips all members of and those seeking accession to the wto have to make available with limited exceptions both product and process patents in every sector including pharmaceuticals more specifically trips provides that all wto members have to receive product patent applications for pharmaceuticals from the date of establishment of the wto i e january 1995 it is important to note that even under the trips regime patents are to be granted only on applications received from 1995 onwards for new patentable pharmaceutical inventions thus prices of existing pharmaceuticals already on the market or even those covered by patent

international business cycles the authors estimate a dynamic two country model in which economic fluctuations are driven by a worldwide supply shock country specific supply shocks and relative fiscal money and preference shocks identification is achieved using only long run restrictions based on a theoretical model the main results are 1 supply shocks particularly country specific ones are very important in generating international business cycles and 2 although the post 1973 flexible exchange rate period has been inherently more volatile there are no differences in transmission properties of economic disturbances across exchange rate regimes for the endogenous variables they focus on copyright 1993 by american economic association

spatial temporal model of insect growth diffusion and derivative pricing insect derivatives represent an important innovation in specialty crop risk management an active over the counter market in insect derivatives will require a transparent pricing method this paper develops an econometric model of the spatio temporal process underlying a particular insect population and develops a pricing model based on this process we show that insect derivatives can play an important risk management role in mitigating b tabaci whitefly damage in cotton beyond developing a new risk management instrument the key methodological contribution of this paper lies in pricing derivatives with stochastic properties in both space and time dimensions copyright 2008 oxford university press

basis convergence and long memory in volatility when dynamic hedging with futures abstractwhen market returns follow a long memory volatility process standard approaches to estimating dynamic minimum variance hedge ratios mvhrs are misspecified simulation results and an application to the s p 500 index document the magnitude of the misspecification that results from failure to account for basis convergence and long memory in volatility these results have important implications for the estimation of mvhrs in the s p 500 example and other markets as well

estimation of the optimal futures hedge standard approaches to designing a futures hedge often suffer from two major problems first they focus only on minimizing risk so no account is taken of the impact on expected return second in estima ting the hedge ratio no allowance is made for time variation in the distribution of cash and futures price changes this paper describes a technique for estimating the optimal futures hedge that corrects these problems and illustrates its use in hedging treasury bonds with t bond futures copyright 1988 by mit press

understanding interdependence the macroeconomics of the open economy list of figureslist of tablesintroduction1the endogeneity of exchange rate regimes32exchange rate behavior under alternative exchange rate arrangements343panel one money for how many 844exchange rates prices and external adjustment in the united states and japan1075the dynamic optimizing approach to the current account theory and evidence1696international capital mobility in the 1990s2017a retrospective on the debt crisis2628trade liberalization in disinflation2919inflation and growth in an integrated approach31310panel the outlook for stabilization and reform in central and eastern europe36811international cooperation in the making of national macroeconomic policies where do we stand 39112the political economy of monetary union44813what do we need to know about the international monetary system 509conference participants531author index535subject index543

the rmb debate empirical analysis on the effects of exchange rate shocks in china and japan for a better understanding of the ongoing debates on the rmb this paper investigates the effects of exchange rate shocks on output and the current account for china and japan we use structural vector auto regression models and find that yen appreciation reduces current account surpluses while having no strong effect on output in japan rmb appreciation on the other hand has an insignificant effect on the current account although it tends to reduce output in china for china dollar pricing with vertical trade integration seems responsible for the insignificant effect on the current account

pricing patent loss and the market for pharmaceuticals dustry the drug price competition and patent term restoration act of 1984 very clearly reflects the determination of policy makers to simultaneously address issues of price control and technical progress the 1984 act increased returns to innovation by extending the period of patent protection to take into account the time between receipt of a patent and food and drug administration fda approval of a drug for sale in the market the 1984 act also reduced the testing requirements for approval of new generic brands of existing chemical entities thus reducing entry barriers in markets where patents have expired the expected outcome from eased entry conditions for generic substitutes was substantially enhanced price competition and lower prices for brand name drugs in fact prices for brand name drugs have tended to increase following entry by generics wagner and duffy 28 examined price changes for top selling generics and name brands they show substantial price increases in brand name prices accompanying large reductions in generic prices as entry of generics occurs grabowski and vernon 9 examined data on 18 major orally administered rug products subject to generic competition between 1983 and 1987 and found that the name brand price increased by an average of 7 one year subsequent to generic entry and 11 two years following generic entry

the de merits of minimum variance hedging application to the crack spread we study the empirical performance of the classical minimum variance hedging strategy comparing several econometric models for estimating hedge ratios of crude oil gasoline and heating oil crack spreads given the great variability and large jumps in both spot and futures prices considerable care is required when processing the relevant data and accounting for the costs of maintaining and re balancing the hedge position we find that the variance reduction produced by all models is statistically and economically indistinguishable from the one for one naive hedge however minimum variance hedging models especially those based on garch generate much greater margin and transaction costs than the naive hedge therefore we encourage hedgers to use a naive hedging strategy on the crack spread bundles now offered by the exchange this strategy is the cheapest and easiest to implement our conclusion contradicts the majority of the existing literature which favours the implementation of garch based hedging strategies

extent and possible causes of intrayear agricultural commodity price volatility wheat corn rice soybeans and cotton experienced higher volatility in the second half of the 2000s for the sample at hand the unit root tests only validate a new period of high volatility for wheat and cotton if in the next couple of years however corn rice and soybeans maintain their higher volatility a new period of high volatility may also be validated statistically regarding the factors driving the intrayear volatility gmm estimates show that commodity market fundamentals i e the stock to use ratio and to a lesser extent the degree of internationalization are the most systematically statistically significant coefficients among commodities over time consecutive low stock to use ratios and a thin international market provoke typically high volatility speculative activity and liquidity in the agricultural derivative market have a stabilizing effect on the spot price if any finally common macro factors significantly impact volatility especially the volatility of petrol and of exchange rates their dispersion importance over the sample is quite sizeable however it is difficult to establish a link between on the one hand loose monetary policy business cycle and inflation and on the other hand commodity price volatility as the sign of the estimated coefficient changes depending on the commodity and the estimated elasticities are quite low

a market equilibrium analysis of the impact of risk on the u s rice industry an economic model of supply demand for u s rice suggests that increases in risk result in decreased acreage and increased marketing margins in a market equilibrium context the empirical results also suggest rice production and rice prices are more responsive to changes in risk faced by marketing firms than changes in risk faced by producing firms

pure martingale and joint normality tests for energy futures contracts abstract in this study we empirically analyze to see if the pure martingale hypothesis holds for three energy related commodities crude oil heating oil and natural gas we also test this hypothesis for five different hedging horizons 1 day 1 week 4 week 8 week and 12 week our empirical results show that the pure martingale hypothesis holds for all three commodities and all five horizons this implies that the expected return on futures contract can be ignored in determining the optimal hedge ratio we also test to see if the joint normality between futures and spot returns holds for the same three commodities and five hedging horizons we reject the joint normality hypothesis for all three commodities and five hedging horizons this implies that hedgers with different utility function have different optimal hedge ratios thus in general one needs to take into account of hedger s utility function when deriving optimal hedge ratio our results are robust to pre and post financial crisis as well as some other specifications considered in the paper

hedging effectiveness of the hedged portfolio the expected utility maximization subject to the value at risk approach multivariate volatilities and distribution play an important role in portfolio selection and can be used to calculate the value at risk var of a multiple asset financial position this study proposes a new expected utility maximization eum model that accounts for var eum model with a var constraint eum var additionally using the eum var model this study investigates the hedging effectiveness of short and long hedged portfolios constructed with multivariate generalized autoregressive conditional heteroscedasticity garch type models that feature level effects and multivariate normal and skewed distributions for stock indexes and their corresponding futures in the greater china region it is found that all else equal portfolios constructed using the multivariate skewed distribution are far more effective in hedging than those that rely on the other distributions and the effectiveness of hedged portfolios from the multivariate garch type models with level effects outperform those without level

optimal hedge ratios at the winnipeg commodity exchange multivariate garch models are employed to estimate time varying hedge ratios for three commodities traded on the winnipeg commodity exchange garch hedge ratios are shown to be superior to those based on the traditional regression approach to calculating the optimal hedge les ratios optimaux de comptant par rapport aux contrats a terme a la bourse de denrees de winnipeg l auteur emploie des modeles multivaries de type garch pour calibrer les ratios optimaux de comptant par rapport aux contrats a terme pour trois denrees transigees a la bourse des denrees de winnipeg ces ratios s averent superieurs a ceux qu on obtient par les methodes de regression traditionnelles

causality and price discovery an application of directed acyclic graphs directed acyclic graphs dag s and error correction models ecm s are employed to analyze questions of price discovery between spatially separated commodity markets and the transportation market linking them together results from our analysis suggest these markets are highly interconnected but it is the inland commodity market that is strongly influenced by both the transportation and commodity export markets however the commodity markets affect the volatility of the transportation market over longer horizons our results suggest that transportation rates are critical in the price discovery process lending support for the recent development of exchange traded barge rate futures contracts

the econometric analysis of models with risk terms summary in this paper we have attempted to provide an integrated approach to the estimation of models with risk terms it was argued that there exist orthogonality conditions between variables in the information set and higher order moments of the unanticipated variable density these could be exploited to provide consistent estimators of the parameters associated with the risk term specifically it was recommended that an iv estimator should be applied with instruments constructed from the information set four existing methods commonly used to estimate models with risk terms are examined and applications of the techniques are made to the estimation of the risk term in the us c exchange market and the effects of price uncertainty upon production

the new wave of private capital inflows push or pull abstract this paper studies the determinants and sustainability of the widespread private capital inflows to middle income countries after 1989 the key question is whether these flows are mostly pulled by attractive domestic conditions or pushed by unfavorable conditions in developed countries an analytical model focusing on country risk is developed and used empirically it is argued that the observed improvement in country creditworthiness is mostly due to the decline in international interest rates and that therefore its importance as a proximate cause does not support the pull interpretation all things considered in most countries the key answer that emerges is push

price and welfare effects of a pharmaceutical substitution reform the price effects of the swedish pharmaceutical substitution reform are analyzed using data for a panel of all pharmaceutical product sold in sweden in 1997 2007 the price reduction due to the reform was estimated to average 10 and was found to be significantly larger for brand name pharmaceuticals than for generics the results also imply that the reform amplified the effect that generic entry has on brand name prices by a factor of 10 results of a demand estimation imply that the price reductions increased total pharmaceutical consumption by 8 and consumer welfare by sek 2 7 billion annually

portfolio capital flows hot or cold a distinction is often made between short term and long term capital flows the former are deemed unstable hot money and the latter are deemed stable cold money using time series analysis of balance of payments data for five industrial and five developing countries we find that in most cases the labels short term and long term do not provide any information about the time series properties of the flow in particular long term flows are often as volatile as short term flows and the time it takes for an unexpected shock to a flow to die out is similar across flows long term flows are also at least as unpredictable as short term flows and knowledge of the type of flow does not improve the ability to forecast the aggregate capital account copyright 1995 by oxford university press

futures cross hedging with a stationary basis when managing risk frequently only imperfect hedging instruments are at hand we show how to optimally cross hedge risk when the spread between the hedging instrument and the risk is stationary for linear risk positions we derive explicit formulas for the hedge error and for nonlinear positions we show how to obtain numerically efficient estimates finally we demonstrate that even in cases with no clear cut decision concerning the stationarity of the spread it is better to allow for mean reversion of the spread rather than to neglect it

estimating the optimal hedge ratio in the presence of potential unknown structural breaks we propose a new approach in the estimation of the optimal hedge ratio that allows the hedge ratio to vary over time but without the necessity of frequently rebalancing the portfolio we apply this in the context of the us and uk equity markets using weekly spot share prices and future share prices during the period 5 january 1999 to 29 september 2009 our method is to test for cointegration in the presence of two potentially unknown structural breaks by determining the timing of each via the underlying data the empirical findings reveal that the spot and future prices are strongly cointegrated in each market the estimated parameters disclose that the optimal hedge ratio is not constant in case of the us and the uk we find one negative and one positive shift in the optimal hedge ratio in the us however we find only one significant and positive shift in the optimal hedge ratio in the uk the implication of these findings from the perspective of both investors as well as policy makers is elaborated on

optimal dynamic hedging portfolios and the currency composition of external debt abstract we present a model which shows that the currency composition of a country s external debt can serve as a hedging instrument against changes in exchange rates and commodity prices because our model permits the second moments to change through time we get a sequence of optimal dynamic hedging portfolios which can be estimated with a multivariate generalized autoregressive conditional heteroskedasticity garch model to illustrate the usefulness of the technique we apply it to indonesia and it is found as expected that indonesia s optimal debt portfolio consists of a much larger proportion of us dollars and a much smaller proportion of japanese yen than they have in their current debt portoflio

regulation of pharmaceutical prices evidence from a reference price reform in denmark reference price systems for prescription drugs constitute widely adopted cost containment tools under these regimes patients co pay a fraction of the difference between a drug s pharmacy retail price and a reference price that is set by the government reference prices are either externally based on drug prices in other countries or internally based on domestic drug prices determined we study the effects of a change from external to internal reference pricing in denmark in 2005 we find that the reform led to substantial reductions in retail prices reference prices and patient co payments as well as to sizable decreases in overall producer revenues and health care expenditures the reform induced consumers to substitute away from branded drugs for which we estimate strong preferences the increase in consumer welfare due to the reform therefore depends on whether or not we take perceived quality differences into account in its calculation

statistical significance of indicators of efficiency and incentives examples from west african agriculture indicators of efficiency and incentives derived from trade theory such as the domestic resource cost coefficient drc and effective protection ep are generally presented as simple means analysis of their distributions using farm data on millet and sorghum production from west africa shows them to be highly variable and in some cases to be significantly skewed the analysis also shows the indicators to be highly elastic to changes in such parameters as input and output prices if this variability is not considered when making inferences from such data policy recommendations can be seriously misleading because they are based on different farming populations

marketing margins market power and price uncertainty this paper provides a conceptual and empirical framework for analyzing marketing margins in a noncompetitive food processing industry facing output price uncertainty the framework allows the decomposition of observed margins into components reflecting the marginal cost of the processing industry oligopoly oligopsony price distortions and an output price risk component the empirical procedure is applied to a time series of spreads between wholesale pork prices and farm prices of market hogs the principal finding is that while farm wholesale margins are more consistent with competitive performance now than they were fifteen years ago the output price risk component persisted throughout the sample period

another look at models of the short term interest rate the short term rate of interest is fundamental to much of theoretical and empirical finance yet no consensus has emerged on the dynamics of its volatility we show that models which parameterize volatility only as a function of interest rate levels tend to over emphasize the sensitivity of volatility to levels and fail to model adequately the serial correlation in condi tional variances on the other hand serial correlation based models like garch models fail to capture adequately the relationship between interest rate levels and volatility we introduce and test a new class of models for the dynamics of short term interest rate volatility which allows volatility to depend on both interest rate levels and information shocks two important conclusions emerge first the sensitivity of interest rate volatility to interest rate levels has been overstated in the literature while this relationship is important adequately modeling volatility as a function of unexpected information shocks is also important sec ond we conclude that the volatility processes in many existing theoretical models of interest rates are misspecified and suggest new paths toward improving the theory

a utility based approach to energy hedging abstract a key issue in the estimation of energy hedges is the hedgers attitude towards risk which is encapsulated in the form of the hedgers utility function however the literature typically uses only one form of utility function such as the quadratic when estimating hedges this paper addresses this issue by estimating and applying energy market based risk aversion to commonly applied utility functions including log exponential and quadratic and we incorporate these in our hedging frameworks we find significant differences in the optimal hedge strategies based on the utility function chosen

the effect of barge and ocean freight price volatility in international grain markets this paper looks at the potential role of time varying volatility of mississippi river barge and ocean freight prices on commodity prices in illinois at the us gulf and in rotterdam using a vector error correction garch in mean model the model is used to infer the extent to which transportation price risk affects price dynamics in international grain markets results from a simulation exercise indicate that both barge and ocean price volatility influence grain prices but barge price volatility tends to have a greater impact on grain prices and marketing margins than that arising from ocean price volatility consistent with most studies that evaluate the role of risk in marketing channels results here suggest that a reduction in barge rate risk would reduce marketing margins between illinois and the us gulf and between the us gulf and rotterdam the existence of an ocean freight futures contract coupled with the lack of a futures contract for barge rates may be partially responsible for the finding that barge rates have a significant influence on grain prices and contribute most to wide marketing margins found throughout the international grain marketing system

managing economic risk in value based marketing of fed cattle this research investigates optimal price risk management strategies for fed cattle producers engaged in grid pricing stochastic simulation is used to determine optimal hedge ratios for fed cattle priced on a live weight basis or on a series of grids that vary in terms of premium discount structure as well as base price results indicate that the optimal hedging strategy is greatly affected by the base price used in a particular grid this has significant implications for pricing efficiency in the cattle market base prices that are linked more closely with downstream markets offer the potential to improve pricing efficiency however the risk associated with these prices is difficult to manage effectively with existing futures instruments

health care is an individual necessity and a national luxury applying multilevel decision models to the analysis of health care expenditures health care is neither a necessity or a luxury it is both since the income elasticity varies with the level of analysis with insurance individual income elasticities are typically near zero while national health expenditure elasticities are commonly greater than 1 0 the debate over whether health care is or is not a luxury good arises primarily from the failure to specify levels of analysis clearly so as to distinguish variation within groups from variation between groups apparently contradictory empirical results are shown to be consistent with a simple nested multilevel model of health care spending