a semiparametric approach to short term oil price forecasting abstract in this paper it is shown how the garch properties of oil price changes can be employed to forecast the oil price distribution over short term horizons the forecasting methodology is semiparametric and it is based on the bootstrap approach the results of an out of sample forecasting exercise carried out using the brent oil price series suggest that the forecasting approach can be used to obtain a performance measure for the forward price in addition to compute interval forecasts for the oil price

growth and defense pooled estimates for the nato alliance 1951 1988 in two provocative and influential contributions emile benoit 4 5 uncovered a net positive association between defense spending and economic growth for 44 less developed countries ldcs during the 1950 65 period apparently a larger defense burden as measured by the share of national income devoted to defense may have promoted growth for these countries this finding was controversial and generated an extensive literature that either found fault with benoit s methodology or else investigated the relationship between growth and defense with alternative methodologies one such methodology relied on an aggregate production function to derive an equation for the sources of growth owing to technological change labor growth investment productivity differences among sectors and externalities this supply side approach was associated with feder 13 and ram 22 when a feder ram model was used researchers typically discovered either a small positive effect or else no impact of defense on growth except for alexander 1 the feder ram approach has been applied to large cross sections of ldcs to cross sections of ldcs and developed countries or to individual countries over time the purpose of this paper is fivefold first we extend the three sector feder ram model to allow for the influence of defense spillin externalities as the defense expenditures of a nation s allies affect the nation s own defense and civilian sectors in either a positive or negative fashion spillin externalities can stem from input complementarity or substitutability procurement practices joint ventures or operational considerations second we check the data for unit roots and when appropriate cointegration these tests help us to avoid a dynamic misspecification third we estimate a three sector feder ram growth equation for each of ten nato allies for the 1951

a note on information seasonality and the disappearance of the weekend effect in the uk stock market the weekend effect in uk stock prices has disappeared in the 1990s beneath the surface however there remain systematic day of the week effects only visible when returns are partitioned by the direction of the market a systematic pattern of market wide news arrivals into the uk stock market is discovered and found to provide an explanation for these day of the week effects

military spending and stochastic growth abstract this study examines capital accumulation military spending arms accumulation and output growth in a stochastic endogenous growth model the analysis shows that higher lower growth in foreign military spending leads to faster slower economic growth in the home country if the home country s intertemporal substitution elasticity in consumption is smaller larger but more volatility in foreign military spending can lead to higher economic growth in the home country when its intertemporal substitution elasticity is large in addition shocks to output production may stimulate economic growth

international evidence on crude oil price dynamics applications of arima garch models abstract we examine the usefulness of several arima garch models for modeling and forecasting the conditional mean and volatility of weekly crude oil spot prices in eleven international markets over the 1 2 1997 10 3 2009 period in particular we investigate the out of sample forecasting performance of four volatility models garch egarch and aparch and figarch over january 2009 to october 2009 forecasting results are somewhat mixed but in most cases the aparch model outperforms the others also conditional standard deviation captures the volatility in oil returns better than the traditional conditional variance finally shocks to conditional volatility dissipate at an exponential rate which is consistent with the covariance stationary garch models than the slow hyperbolic rate implied by the figarch alternative

monetary anticipations and the demand for money reply to mackinnon and milbourne abstract mackinnon and milbourne 1984 in an extended comment on carr and darby 1981 claim that money supply shocks do not enter the money demand function for the united states this reply discusses the economic and econometric errors which led to this conclusion and presents further empirical evidence in support of our approach

the impact of military burden on long run growth and welfare abstract this paper presents an endogenous growth model to examine how a government s resource allocation between the defense and non defense sectors will govern both economic growth and social welfare we demonstrate that there exists an optimal defense expenditure share that maximizes the economic growth rate but this rate is smaller than the welfare maximizing share this result can be viewed as a possible vehicle to explain why in many developing countries arms limitation and disarmament negotiations usually have low performance even failing

oil price shocks and real gdp growth empirical evidence for some oecd countries this study assesses empirically the effects of oil price shocks on the real economic activity of the main industrialized countries multivariate var analysis is carried out using both linear and non linear models the latter category includes three approaches employed in the literature namely the asymmetric scaled and net specifications evidence of a non linear impact of oil prices on real gdp is found in particular oil price increases are found to have an impact on gdp growth of a larger magnitude than that of oil price declines with the latter being statistically insignificant in most cases among oil importing countries oil price increases are found to have a negative impact on economic activity in all cases but japan moreover the effect of oil shocks on gdp growth differs between the two oil exporting countries in the sample with the uk being negatively affected by an oil price increase and norway benefiting from it

an ex ante view of household portfolio choice the role of expected capital gains this paper highlights an issue not previously addressed in portfolio balance modelling the impact of assetspecific expected capital gains on the composition of the household wealth portfolio we extend the brainard tobin portfolio choice model to incorporate the distinction between expected and unexpected capital gains and estimate two versions of the model while our specification is more appealing on a theoretical basis we were unable to distinguish clearly between the ex ante and ex post models given currently available data

forecasting volatility of crude oil markets abstract this article investigates the efficacy of a volatility model for three crude oil markets brent dubai and west texas intermediate wti with regard to its ability to forecast and identify volatility stylized facts in particular volatility persistence or long memory in this context we assess persistence in the volatility of the three crude oil prices using conditional volatility models the cgarch and figarch models are better equipped to capture persistence than are the garch and igarch models the cgarch and figarch models also provide superior performance in out of sample volatility forecasts we conclude that the cgarch and figarch models are useful for modeling and forecasting persistence in the volatility of crude oil prices

fiscal faux pas an analysis of the revenue implications of trade liberalization abstract this paper examines the argument that trade liberalization depresses tax revenue gdp ratios in developing countries this occurs because the structural characteristics associated with developing countries limit their ability to make the transition from trade to domestic taxes using a panel of 80 developing and industrialized countries over 1970 98 the econometric analysis carried out employs a fixed effects regression framework to examine the evidence the results indicate that low income and upper middle income countries have experienced declining tax revenues as a result of falling income and trade tax revenues and that structural characteristics have been significant in explaining the decline

an examination of the robustness of the weekend effect this paper analyzes the robustness of the day of the week dow and weekend effects to alternative estimation and testing procedures the results show that sample size can distort the interpretation of classical test statistics unless the significance level is adjusted down ward specification tests reveal widespread departures from ols assumptions hypothe sis tests results are reported using robust econometric methods and a garch model the strength of the dow and weekend effect evidence appears to depend on the estimation and testing method both effects seem to have disappeared by 1975

oil prices and real exchange rates in this paper we investigate the long run relationship between real oil prices and real exchange rates by using a monthly panel of g7 countries from 1972 1 to 2005 10 we first test whether exchange rates are cointegrated with real oil prices it is shown that real oil prices may have been the dominant source of real exchange rate movements and that there is a link between real oil prices and real exchange rates we then examine the ability of real oil prices to forecast future real exchange returns panel predictive regression estimates suggest that real oil prices have significant forecasting power the out of sample prediction performances demonstrate greater predictability over longer horizons

military expenditures and economic growth in less developed countries an augmented model and further evidence a study of the impact of military expenditures on economic growth and development examines the differences in the results of previous studies which led to contradictory conclusions the authors find that these differences are due to sample variations specificational choices and the different time periods examined the data indicate that there is no consistent statistically significant connection between military spending and economic growth augmentation of the models suggests that military expenditures neither help nor hurt economic growth to any significant extent 2 tables

monetary anticipations and the demand for money abstract it has recently been argued that unanticipated changes in nominal money supply should affect the real demand for money and empirical results which appear to support this hypothesis have been presented unfortunately the econometric techniques used by previous authors yield severel biased estimates in this paper we show how valid estimates may easily be obtained and present some illustrative empirical results using u s data these results do not support the conclusions of earlier authors we find that unanticipated money supply changes do indeed affect the real demand for money but with the wrong sign and that anticipated changes also have a significant effect a consistency test for all models employing the anticipated unanticipated distinction is also proposed

dynamic models of portfolio behavior more on pitfalls in financial model building in an important article in this review william brainard and james tobin have emphasized the role played by the wealth constraint in systems of asset demand equations the wealth constraint gives rise to consistency conditions which must be satisfied by the demand functions when such a system is specified and estimated as brainard and tobin caution care must be taken to ensure that unrealistic coefficients are not inadvertently imposed on omitted equations by failure to recognize the consistency conditions noting that the wealth constraint applies out of as well as in portfolio equilibrium brainard and tobin focus attention on systems in which actual and desired stocks of assets differ they specify a multivariate stock adjustment model wherein the desired change in holdings of any asset depends in general upon all asset stock disequilibria the existence of such stock disequilibria can be implicitly rationalized on the basis of costs of adjustment which impinge on the rate of change of at least some assets in this framework they show that the stock adjustment coefficients must also satisfy certain consistency conditions to ensure that the wealth constraint is satisfied an important feature of their analysis is that the total change in wealth savings plus capital gains is treated as exogenous to the financial sector and the asset flow demands described above are conditional upon the exogenously given change in wealth this strategy of separating the portfolio balance decision from the consumption saving decision is one that tobin has explicitly used and justified in his 1969 article especially pp 15 16 and is one that has been widely and effectively used in modern macroeconometric models the central argument of the present paper is that this separation of flow allocation and stock allocation decisions is not legitimate in the presence of adjustment costs attached to changing the level of individual asset holdings the existence of adjustment costs means that there is no portfolio balance problem per se in the sense of allocation of a given level of wealth but rather a longer run problem of determining an optimal time path for each asset and for the level of consumption thus a natural extension of the brainard tobin model is to treat saving and portfolio decisions in an integrated fashion 2 note that the brainard tobin model is perfectly consistent with any model of savings behavior and hence no logical con queen s university and cowles foundation for research in economics yale university i am grateful to adrian pagan gordon sparks and james tobin for helpful discussions and especially to gary smith who as well as patiently discussing many of the issues provided detailed comments on earlier drafts of this paper this research was partially supported by a national science foundation grant to the cowles foundation and by a canada council grant to the author remaining mistakes and opinions are my own i this also has implications for the common practice in macro economic models of leaving the bond market as implicit care must be taken to ensure that silly behavior is not inadvertently attributed to bondholders william silber tobin and alan blinder and robert solow have initiated research which reintroduces the bond market into macroeconomic models 21t appears to be a fairly general result that the existence of adjustment costs leads to integrated behavior m ishaq nadiri and sherwin rosen have established a similar result for the theory of the firm and robin mukherjee and edward zabel have recently shown that the separation theorem prominent in the finance literature on the mean variance approach to optimal consumption portfolio behavior fails to hold when transactions costs are introduced in my 1975 paper appendix i have argued that the integration of saving and portfolio balance decisions also applies in continuous time models even though such models are characterized by separate stock and flow budget constraints

modelling oil price volatility in this paper we examine the volatility of crude oil price using daily data for the period 1991 2006 our main innovation is that we examine volatility in various sub samples in order to judge the robustness of our results our main findings can be summarised as follows 1 across the various sub samples there is inconsistent evidence of asymmetry and persistence of shocks and 2 over the full sample period evidence suggests that shocks have permanent effects and asymmetric effects on volatility these findings imply that the behaviour of oil prices tends to change over short periods of time

the efficiency of the crude oil markets evidence from variance ratio tests this study examines the random walk hypothesis for the crude oil markets using daily data over the period 1982 2008 the weak form efficient market hypothesis for two crude oil markets uk brent and us west texas intermediate is tested with non parametric variance ratio tests developed by wright j h 2000 alternative variance ratio tests using ranks and signs journal of business and economic statistics 18 1 9 and belaire franch j and contreras d 2004 ranks and signs based multiple variance ratio tests working paper department of economic analysis university of valencia as well as the wild bootstrap variance ratio tests suggested by kim j h 2006 wild bootstrapping variance ratio tests economics letters 92 38 43 we find that the brent crude oil market is weak form efficiency while the wti crude oil market seems to be inefficiency on the 1994 2008 sub period suggesting that the deregulation have not improved the efficiency on the wti crude oil market in the sense of making returns less predictable

gasoline prices gasoline consumption and new vehicle fuel economy evidence for a large sample of countries abstract countries differ considerably in terms of the price drivers pay for gasoline this paper uses data for 132 countries for the period 1995 2008 to investigate the implications of these differences for the consumption of gasoline for road transport to address the potential for simultaneity bias we use both a country s oil reserves and the international crude oil price as instruments for a country s average gasoline pump price we obtain estimates of the long run price elasticity of gasoline demand of between 0 2 and 0 5 using newly available data for a sub sample of 43 countries we also find that higher gasoline prices induce consumers to substitute to vehicles that are more fuel efficient with an estimated elasticity of 0 2 despite the small size of our elasticity estimates there is considerable scope for low price countries to achieve gasoline savings and vehicle fuel economy improvements via reducing gasoline subsidies and or increasing gasoline taxes

long run gasoline demand for passenger cars the role of income distribution it is commonly agreed that the level of income and prices are crucial determinants of the consumption of motor gasoline the respective long run price and income elasticities are regularly calculated using cross sectional models despite the acknowledgement of the role of income distribution it plays no role in intercountry cross sectional models this is due to a lack of appropriate data this paper shows that the omission of distributional characteristics provides misleading elasticities using available distributional measures this paper is referring to an income threshold which is crucial to the acquisition of an automobile it is shown that on the one hand in poor countries an unequal income distribution is needed to enable at least some people to buy automobiles on the other hand in wealthy countries an unequal income distribution would exclude some people from acquiring automobiles hence depending on the income level inequality has a diverging impact on the ability to buy durable goods the second part of this paper develops a pooled 90 country model to examine this approach empirically it could be shown that distribution variables are highly significant to explain the demand for automobiles and motor gasoline moreover the consideration of the distribution of income leads to a considerable decrease in income elasticity values this is mainly due to the positive correlation between income level and income equality within the sample

estimating oil price value at risk using the historical simulation approach abstract in this paper we propose using value at risk var for oil price risk quantification var provides an estimation for the maximum oil price change associated with a likelihood level and can be used for designing risk management strategies we analyse three var calculation methods the historical simulation standard approach the historical simulation with arma forecasts hsaf approach developed in this paper and the variance covariance method based on autoregressive conditional heteroskedasticity models forecasts the results obtained indicate that hsaf methodology provides a flexible var quantification which fits the continuous oil price movements well and provides an efficient risk quantification

the asymmetry of the impact of oil price shocks on economic activities an application of the multivariate threshold model this paper applies the multivariate threshold model to investigate the impacts of an oil price change and its volatility on economic activities changes in industrial production and real stock returns the statistical test on the existence of a threshold effect indicates that a threshold value does exist using monthly data of the us canada and japan during the period from 1970 to 2002 we conclude i the optimal threshold level seems to vary according to how an economy depends on imported oil and the attitude towards adopting energy saving technology ii an oil price change or its volatility has a limited impact on the economies if the change is below the threshold levels iii if the change is above threshold levels it appears that the change in oil price better explains macroeconomic variables than the volatility of the oil price and iv if the change is above threshold levels a change in oil price or its volatility explains the model better than the real interest rate

daily seasonality in crude oil returns and volatilities abstract in this article we test for the existence of daily seasonality in returns and volatilities of crude oil using a dummy augmented garch specification for the period from may 1987 to october 2013 our key findings are as follows i volatilities on mondays are significantly higher than on all other weekdays providing the important insight that seasonal effects should be considered when forecasting crude oil volatility ii returns on the other hand tend to be lower on mondays than on other weekdays suggesting profitable investment strategies based on this seasonal pattern in fact the analysis of a simple long short trading rule based on the monday effect provides some evidence that it can outperform a passive buy and hold approach however it cannot do so to an extent that is statistically significant iii our seasonality results are fairly robust to the choice of other frequently used garch model variants like garch m tgarch and cgarch

testing for financial buffer stocks in sectoral portfolio models empirical implementation of the buffer stock money notion tends to concentrate either on the shock absorber aspects or the spillover disequilibrium money aspects but rarely combines both moreover a potential buffer role for nonmoney assets is usually precluded without explicit empirical testing this paper examines the role of financial buffers in an ex ante sectoral model of expenditure and portfolio behavior incorporating both the shock absorber and spillover aspects in terms of cross equation parameter restrictions these are tested for a range of different assets and liabilities using quarterly data for the u k personal sector copyright 1990 by mit press

are the crude oil markets becoming weakly efficient over time a test for time varying long range dependence in prices and volatility this paper analyzes the efficiency of crude oil markets brent and west texas intermediate by means of estimating the fractal structure of these time series we test for time varying degrees of long range dependence using the rescaled range hurst analysis and find evidence that this market has become more efficient over time these results are robust for controlling for short term autocorrelation by means of a shuffling procedure

an analysis of factors affecting price volatility of the us oil market abstract this paper studies the price volatility of the crude oil market by examining the market structure of opec the stable and unstable demand structure and related elasticity of demand in particular the impacts of prosperity and recession of the world economy and the resulting demand shift on crude oil price are investigated the error correction model is used to estimate the demand relations and related elasticity the income effect on demand functions is evaluated to shed light on future prices a simulation of potential oil prices under different scenarios on a cut of one million barrels per day by opec is evaluated from our simulation given the 4 cut in opec production the oil price is expected to increase unless the recession is severe the magnitude and scope of a price hike would be diminished if non opec or domestic production were greatly expanded

sufficient conditions for expected utility to imply drawdown based performance rankings the least restrictive sufficient condition for expected utility to imply sharpe ratio rankings is the location and scale ls condition see meyer 1987 the ls condition includes the normal and many other asymmetric and leptokurtic distributions commonly used in finance in this paper we argue that this condition is also sufficient for expected utility to imply drawdown based performance measure rankings because for investment funds satisfying the ls condition it does not matter whether funds are ranked with the sharpe ratio or with a drawdown based performance measure as the rankings are identical hence the same conditions that provide an expected utility foundation for the sharpe ratio also provide an expected utility foundation for drawdown based performance measures theoretically drawdown based performance measures are as good as the sharpe ratio

a markov switching model of the conditional volatility of crude oil futures prices abstract this paper examines the temporal behaviour of volatility of daily returns on crude oil futures using a generalised regime switching model that allows for abrupt changes in mean and variance garch dynamics basis driven time varying transition probabilities and conditional leptokurtosis this flexible model enables us to capture many complex features of conditional volatility within a relatively parsimonious set up we show that regime shifts are clearly present in the data and dominate garch effects within the high volatility state a negative basis is more likely to increase regime persistence than a positive basis a finding which is consistent with previous empirical research on the theory of storage e g fama and french 1988a fama and french 1988b and ng and pirrong 1994 the volatility regimes identified by our model correlate well with major events affecting supply and demand for oil out of sample tests indicate that the regime switching model performs noticeably better than non switching models regardless of evaluation criteria we conclude that regime switching models provide a useful framework for the financial historian interested in studying factors behind the evolution of volatility and to oil futures traders interested short term volatility forecasts

the role of money supply shocks in the short run demand for money abstract previous money demand models are either inconsistent with contemporaneous adjustment of the price level to expected changes in the nominal money supply or imply implausible interest rate fluctuations in response to innovations in nominal money we propose a shock absorber money demand model in which money supply shocks affect the synchronization of asset transactions and so engender a temporary increase or decrease in desired money holdings expected changes do not engender such fluctuations in real money inventories in simultaneous estimates for eight industrial countries the shock absorber model proved empirically superior

government size and economic growth a new framework and some evidence from cross section and time series data a study of the impact of government size on economic performance and growth is important theoretically one point of view suggests that a larger government size is likely to be detrimental to efficiency and economic growth because for example i government operations are often conducted inefficiently ii the regulatory process imposes excessive burdens and costs on the economic system and iii many of government s fiscal and monetary policies tend to distort economic incentives and lower the productivity of the system at the other extreme one can identify some points of view that assign to the government a critical role in the process of economic development and could argue that a larger government size is likely to be a more powerful engine of economic development there are several arguments on which the latter point of view is based these include besides others i role of the government in harmonizing conflicts between private and social interests ii prevention of exploitation of the country by foreigners and iii securing an increase in productive investment and providing a socially optimal direction for growth and development

forecasting crude oil market volatility further evidence using garch class models abstract this paper extends the work of kang et al 2009 we use a greater number of linear and nonlinear generalized autoregressive conditional heteroskedasticity garch class models to capture the volatility features of two crude oil markets brent and west texas intermediate wti the one five and twenty day out of sample volatility forecasts of the garch class models are evaluated using the superior predictive ability test and with more loss functions unlike kang et al 2009 we find that no model can outperform all of the other models for either the brent or the wti market across different loss functions however in general the nonlinear garch class models which are capable of capturing long memory and or asymmetric volatility exhibit greater forecasting accuracy than the linear ones especially in volatility forecasting over longer time horizons such as five or twenty days

separating bric using islamic stocks and crude oil dynamic conditional correlation and volatility spillover analysis abstract this paper explores the dynamic conditional correlation and volatility linkage between islamic indexes and oil for bric countries correlations between these assets increase during the global financial crisis for india and china but not for brazil and russia the volatility error forecast variance of all five indexes comes from spillover but is much lower compared to volatility spillover between conventional indexes and oil hedging performance of islamic indexes are superior in india and china compared to conventional indexes in emerging markets an optimal minimum variance portfolio without reducing expected return can be achieved by investing in lower weights of bric islamic indexes and oil compared to conventional indexes

gasoline demand in the oecd an application of pooling and testing procedures abstract this study utilizes a pooled inter country data set finding the long run price elasticity falls in the range 0 55 to 0 9 depending on the choice of pooled estimators the estimators included the ols within and between country estimators plus five feasible gls estimators even allowing for a ten year distributed lag on price to reflect changes in auto efficiency characteristics the within country estimator yields appreciably more inelastic estimates than did the o s estimator which was heavily influenced by the between or inter country variation this difference raises intriguing questions for future research

monetary anticipation and the demand for money in the u k testing rationality in the shock absorber hypothesis the carr darby shock absorber hypothesis that unanticipated changes in the money supply cause changes in real balances but anticipated changes have a unit impact on the price level and therefore leave real balances unchanged is tested using two step and joint estimation techniques for the u k two step methods appear to support the shock absorber hypothesis but the superior joint estimation technique decisively rejects the hypothesis particularly the implicit rational expectations cross equation restrictions

oil and energy price volatility it is commonly believed that since the 1973 oil crisis oil and energy prices have been more volatile than other commodity prices this study examines monthly producer prices for thousands of products over the period january 1945 through august 2005 the results show that crude oil refined petroleum and natural gas prices are more volatile than prices for about 95 of products sold by domestic producers relative to crude commodities however crude oil prices are currently more volatile than about 65 of other products and oil price volatility first exceeded the median for crude commodities following the 1986 drop in oil prices

energy risk management and value at risk modeling abstract the value of energy trades can change over time with market conditions and underlying price variables the rise of competition and deregulation in energy markets has led to relatively free energy markets that are characterized by high price shifts within oil markets the volatile oil price environment after opec agreements in the 1970s requires a risk quantification value at risk has become an essential tool for this end when quantifying market risk there are various methods for calculating value at risk the methods we introduced in this paper are historical simulation arma forecasting and variance covariance based on garch modeling approaches the results show that among various approaches the hsaf methodology presents more efficient results so that if the level of confidence is 99 the value at risk calculated through hsaf methodology is greater than actual price changes in almost 97 6 percent of the forecasting period

a decision theoretic foundation for reward to risk performance measures abstract in this paper we prove that partial moments based performance measures e g omega kappa upside potential ratio sortino satchell ratio farinelli tibiletti ratio value at risk based performance measures e g var ratio cvar ratio rachev ratio generalized rachev ratio and other admissible performance measures are a strictly increasing function in the sharpe ratio the theoretical basis of this result is the location and scale property and two other plausible and mild conditions our result provides a decision theoretic foundation for all these frequently used performance measures moreover it might explain the empirical finding that all these measures typically lead to very similar rankings

the energy demand in the british and german industrial sectors heterogeneity and common factors abstract this paper estimates energy demands for the german and british industrial sectors over the 1978 2004 and the 1991 2004 samples from time series models we can conclude that there is a considerable variation in the value of the coefficients across sectors even though energy demands with sensible parameters can rarely be estimated when using a panel approach the ability of some estimators to allow for diversity across subsectors was an important factor in explaining the estimates for price elasticity on the other hand correlation across panel members or common factors did not markedly influence our results with regard to the estimated parameters our preferred choice for elasticity of economic activity and price in the longer sample is 0 52 and 0 64 similar values are found in the case of the shorter samples bearing in mind the high price elasticity energy taxes can be considered an effective strategy for reducing energy consumption

market risk in commodity markets a var approach we put forward value at risk models relevant for commodity traders who have long and short trading positions in commodity markets in a 5 year out of sample study on aluminium copper nickel brent crude oil and wti crude oil daily cash prices and cocoa nearby futures contracts we assess the performance of the riskmetrics skewed student aparch and skewed student arch models while the skewed student aparch model performs best in all cases the skewed student arch model delivers good results and its estimation does not require non linear optimization procedures as such this new model could be relatively easily integrated in a spreadsheet like environment and used by market practitioners

pricing the european option to switch between two energy sources an application to crude oil and natural gas we consider a firm which can choose between crude oil and natural gas to run its business the firm selects the energy source which minimizes its energy or production costs at a given time horizon assuming the energy strategy to be established over a fixed time window the energy choice decision will be made at a given future date t in this light the firm s energy cost can be considered as a long position in a risk free bond by an amount of the terminal oil price and a short position in a european put option to switch from oil to gas by an amount of the terminal oil price too as a result the option to switch from crude oil to natural gas allows for establishing a hedging strategy with respect to energy costs modeling stochastically the underlying asset of the european put we propose a valuation formula of the option to switch and calibrate the pricing formula to empirical data on a daily basis hence our innovative framework handles widely the hedge against the price increase of any given energy source versus the price of another competing energy source i e minimizing energy costs moreover we provide a price for the cost reducing effect of the capability to switch from one energy source to another one i e hedging energy price risk

the buffer stock notion in monetary economics not the least of harry johnson s contributions to our discipline was the series of survey papers on aspects of monetary economics which he produced during the 1960s and 1970s it is no exaggeration to say that the way in which the literature of monetary economics is organised even now follows the design which johnson first set out in 1962 and built on in the subsequent decade nevertheless the subject has not stood still and one of the more interesting developments of the last few years has involved the introduction of what has been variously described as the disequilibrium money shock absorber or as i prefer to call it the buffer stock notion into monetary economics the development of this line of thought was getting underway before johnson s untimely death much of it indeed under the auspices of his own research programme at the lse even so this did not happen early enough for the relevant ideas to be put in their proper niche by johnson himself and the buffer stock approach is not yet fully integrated into the mainstream of monetary economics much of the relevant literature is empirical concerned with modelling particular aspects of the monetary experience of specific countries hence it is fragmented and contains few papers which attempt a coherent account of just what this approach is and how it relates to other approaches to monetary analysis although essays by goodhart 1982a b and judd and scadding 1982a contain important discussions of these issues to the best of my knowledge only jonson 1976a and knoester 1979a have devoted entire papers solely to this central issue and these are relatively inaccessible and hence less widely known than they deserve to be in this lecture i shall attempt to give a brief account of the essentials of this approach first i shall sketch out its microeconomic background and then i shall discuss those theoretical characteristics which differentiate it from the neo austrian analysis of robert e lucas jr and his associates as well as from the conventional keynesian approach to monetary economics last but by no means least i shall argue that it yields simple theoretical insights into important empirical and policy related issues which are troublesome for alternative approaches in short my tribute to harry

unit root properties of crude oil spot and futures prices in this article we examine whether wti and brent crude oil spot and futures prices at 1 3 and 6 months to maturity contain a unit root with one and two structural breaks employing weekly data over the period 1991 2004 to realise this objective we employ lagrange multiplier lm unit root tests with one and two endogenous structural breaks proposed by lee and strazicich 2003 minimum lagrange multiplier unit root test with two structural breaks review of economics and statistics 85 1082 1089 2004 minimum lm unit root test with one structural break working paper no 04 17 department of economics appalachian state university we find that each of the oil price series can be characterised as a random walk process and that the endogenous structural breaks are significant and meaningful in terms of events that have impacted on world oil markets

superstitious seasonality in precious metals markets evidence from garch models with time varying skewness and kurtosis in this article we analyse whether the friday the 13th effect documented by kolb and rodriguez 1987 can be observed in precious metals markets specifically we use dummy augmented garch models to investigate the impact of this specific calendar day on the conditional means of gold silver palladium and platinum returns the specification of the garch model follows a flexible class recently proposed by leon et al 2005 that incorporates time varying skewness and kurtosis by applying a gram charlier series expansion of the normal density function our results for the period from july 1996 to august 2013 provide three important insights first there is no evidence that human superstition regarding bad luck fridays affects precious metals markets in a negative way i e returns on fridays the 13th are not significantly lower than on regular fridays second besides showing robustness in a variety of settings we can confirm this main result in a sensitivity check where we replace the dummy variables

transmission of shocks and contagion from u s to mena equity markets the role of oil and gas markets abstract using a multifactor model augmented with oil and gas returns this paper examines contagion from the us to mena equity markets and studies the role of energy price fluctuations in amplifying the dependence between the us and mena equity markets we provide empirical evidence of a strong contagion effect originating from the us to mena equity markets the regional oil and gas factors account for the bulk of the variance of the mena equity returns and our findings suggest that the oil and gas markets play an important role in strengthening the dependence between the mena and us markets during episodes of market turmoil we discuss the policymaking importance of our results and propose a strategy to curb the adverse effects of us return shocks on mena equity markets during episodes of stress