quantile dependence of oil price movements and stock returns we examine the impact of quantile and interquantile oil price movements on different stock return quantiles by testing the hypothesis of equality in conditional and unconditional quantile distribution functions of stock returns we capture quantile dependence under different stock market conditions while taking into account different kinds of oil price movements by computing unconditional and conditional stock return quantiles through marginal models for stock returns and copula functions for oil stock dependence analyzing stock return data for three developed economies the us the uk and the european monetary union and the five brics countries brazil russia india china and south africa for 2000 to 2014 our results indicate that 1 the impact of extreme upward and downward oil price changes on upper and lower stock price quantiles was much smaller before compared to after crisis onset 2 the downside spillover effects were larger than the upside spillover effects for most countries before crisis onset and for all countries after crisis onset and 3 small positive and negative oil price movements had no impact on any stock return quantiles neither before nor after crisis onset

the impact of crude oil prices on financial market indicators copula approach abstract oil price changes have varying impacts on the financial indicators of global markets and economies this study aims to explore the dependence structure between crude oil prices and stock market indices as well as the exchange rates in a number of economies categorized with respect to their status as developing emerging markets and oil importer exporter countries dependence structures in this study are evaluated in considerable depth using copula models the broad time period covered allows the investigation of the effect of global financial crisis on the mentioned dependence structure an additional feature of this study is the inclusion of 1 to 30 day analysis to capture the variation of dependence on duration change to serve these aims as well as arima and garch models various copula measures are used to illustrate the level of the association additionally a special focus on the turkish case is given to illustrate its sensitivity to oil prices we find that exchange rates and stock indices of most oil exporter countries show higher oil price dependency whereas emerging oil importer markets are less vulnerable to price fluctuations considerable impacts were found for the global crisis and the continuing recent sharp decrease in oil prices

competitive pricing by a price leader we examine the problem of pricing in a market where one brand acts as a price leader we develop a procedure to estimate a leader s price rule which is optimal given a sales target objective and allows for the inclusion of demand forecasts we illustrate our estimation procedure by calibrating this optimal price rule for both the leader and the follower using data on past sales and prices from the mid size sedan segment of the u s automobile market our results suggest that a leader follower system stackelberg seems more consistent with the pricing behavior in this market than a mutually independent pricing rule nash we also find that our optimal price rule explains this market data better than other pricing schemes that do not account for optimizing behavior on the part of the leader and the follower

co movement of international crude oil price and indian stock market evidences from nonlinear cointegration tests this article explores nonlinear cointegration between international crude oil price and indian stock market in a multivariate framework for the period january 2 2003 to july 29 2011 by threshold cointegration tests which determine the structural breaks endogenously the tests reject any long run equilibrium relationship among the variables for the entire data span in order to get better insight threshold cointegration tests have been applied on three sub phases prior phase i and post phase iii to most volatile phase phase ii spanning from july 2 2007 to dec 29 2008 the tests suggest existence of cointegration in phase iii only toda yamamoto version of granger causality tests reveals that movements of international crude oil price have impact on indian stock market in phases ii and iii with no feedback effect the findings also suggest that global crude oil price is exogenously determined

oil volatility and sovereign risk of brics abstract we study the dependence between oil implied volatility shocks and brics sovereign risk from july 2009 to march 2017 first we examine spillovers in value at risk using multivariate regression quantiles and reveal that oil volatility represents a common risk for oil exporting and oil importing brics countries we also employ a quantile impulse response function and reveal the presence of an asymmetry in the mechanisms of shock transmissions between oil exporters russia and brazil and oil importers china and india the former are more sensitive to positive oil shocks whereas the latter are more sensitive to negative oil shocks second we measure the directional predictability in the quantiles using the bivariate cross quantilogram approach and show that in most cases a low high volatility of oil market predicts low high sovereign risk at various quantiles and lags policy implications are discussed

risk spillovers between oil and stock markets a var for var analysis abstract this article investigates the risk spillover effect between oil and stock markets using a novel multivariate quantile model i e the var for var approach and pseudo impulse response functions we explore the risk spillover at different quantiles using daily data over the period from january 4 2000 through august 31 2018 our results indicate the asymmetry in spillover effect which is significant at upside quantiles but not significant at downside quantiles based on subsample analysis we find that the risk spillover becomes stronger after 2008 financial crisis while before the crisis the spillover effect is very weak the international evidence shows that the asymmetric risk spillover can also be found in other six major stock indices of the g7 group

endogeneity in brand choice models applications of random utility models to scanner data have been widely presented in marketing for the last 20 years one particular problem with these applications is that they have ignored possible correlations between the independent variables in the deterministic component of utility price promotion etc and the stochastic component or error term in fact marketing mix variables such as price not only affect brand purchasing probabilities but are themselves endogenously set by marketing managers this work tests whether these endogeneity problems are important enough to warrant consideration when estimating random utility models with scanner panel data our results show that not accounting for endogeneity may result in a substantial bias in the parameter estimates

asymmetric increasing trends in dependence in international equity markets abstract this paper investigates asymmetric increasing trends in dependence in major international equity markets to this end we develop a multiple regime smooth transition copula garch model and address several important questions including the number of regimes and the existence of increasing asymmetric trends in dependence our results suggest that two or three regimes are sufficient for describing the dependence trends in international equity markets over the last 35 years with significant asymmetric increases in addition the implied time series of three dependence measures show a wide variety of dynamics demonstrating the usefulness of our framework to describe asymmetric increasing dependence trends finally we evaluate the economic significance of our empirical finding based on the 99 value at risk and expected shortfall our result indicates that both risk measures have increased approximately 20 over the last 35 years in major equity markets

volatility spillovers between oil prices and stock sector returns implications for portfolio management abstract in this article we take a recent generalized var garch approach to examine the extent of volatility transmission between oil and stock markets in europe and the united states at the sector level the empirical model is advantageous in that it typically allows simultaneous shock transmission in the conditional returns and volatilities insofar as volatility transmission across oil and stock sector markets is a crucial element for portfolio designs and risk management we also analyze the optimal weights and hedge ratios for oil stock portfolio holdings with respect to the results our findings point to the existence of significant volatility spillover between oil and sector stock returns however the spillover is usually unidirectional from oil markets to stock markets in europe but bidirectional in the united states our back testing procedures finally suggest that taking the cross market volatility spillovers estimated from the var garch models often leads to diversification benefits and hedging effectiveness better than those of commonly used multivariate volatility models such as the ccc garch of bollerslev 1990 the diagonal bekk garch of engle and kroner 1995 and the dcc garch of engle 2002

a study of cartel stability the joint executive committee 1880 1886 this article employs weekly time series data on the joint executive committee railroad cartel from 1880 to 1886 to test empirically the proposition that observed prices reflected switches from collusive to noncooperative behavior an equilibrium model of dynamic oligopoly with asymmetric firms together with explicit functional form assumptions about costs and demand determines the estimating equations and stochastic structure of the econometric model the hypothesis that no switch took place so that price and quantity movements were solely attributable to exogenous shifts in the demand and cost functions is then tested against this alternative and rejected

oil and stock market momentum abstract this study provides a novel perspective to the oil stock market nexus by examining the predictive ability of oil return and volatility on stock market momentum in china we find that oil return volatility serves as a strong predictor of industry momentum even after controlling for stock market state volatility and key macroeconomic variables we argue that the predictive ability of oil over momentum payoffs is driven by time varying investor sentiment that relates to excess buying pressure on winner stocks during uncertain times captured by oil return volatility our tests also show that an oil based momentum strategy wherein the investor conditions the trade on the state of oil return volatility yields significant abnormal returns more than double that could be obtained from the conventional momentum strategy in short the findings suggest that oil market dynamics can contribute to stock market inefficiencies in such a way that these inefficiencies create significant abnormal profits for active managers

oil and the macroeconomy since world war ii all but one of the u s recessions since world war ii have been preceded typically with a lag of around three fourths of a year by a dramatic increase in the price of crude petroleum this does not mean that oil shocks caused these recessions evidence is presented however that even over the period 1948 72 this correlation is statistically significant and nonspurious supporting the proposition that oil shocks were a contributing factor in at least some of the u s recessions prior to 1972 by extension energy price increases may account for much of post opec macroeconomic performance

the directional volatility connectedness between crude oil and equity markets new evidence from implied volatility indexes in this paper we use a set of newly introduced implied volatility indexes to investigate the directional connectedness between oil and equities in eleven major stock exchanges around the globe from 2008 to 2015 the inference on the oil equity implied volatility relationships depends on diebold and yilmaz 2012 2014 2015 who proposed a set of directional measures that enable the dynamic and directional characterization of the relationships among financial variables we find uniform results across the sample countries indicating that the connectedness between oil and equity is established by the bi directional information spillovers between the two markets however we find that the bulk of association is largely dominated by the transmissions from the oil market to equity markets and not the other way around the pattern of transmissions is varying over the sample period however most of the linkages between oil and equities are established from the mid of 2009 to the mid of 2012 which is a period that witnessed the start of global recovery

exogenous shocks and the spillover effects between uncertainty and oil price this paper evaluates the information spillover between equity related uncertainty and the oil price before and after the 2008 global financial crisis and the effects of exogenous shocks on the pattern of information spillover in particular we investigate mean and volatility spillovers between uncertainty and the oil price with and without exogenous shocks by using a bivariate egarch model there are two main findings in our paper first the evidence ensures significant information transmission between equity related uncertainty and the oil price and shows remarkable differences in transmission patterns before and after the crisis second the results show that exogenous shocks can intensify information transmission between oil prices and uncertainty in terms of both the mean and volatility spillover effects moreover exogenous shocks exhibit direct spillover effects on oil prices

oil price volatility and stock returns in the g7 economies this study examines the relationship between oil price volatility and stock returns in the g7 economies canada france germany italy japan the uk and the us using monthly data for the period 1970 to 2014 in order to measure oil volatility we consider alternative specifications for oil prices world nominal and real prices we estimate a vector autoregressive model with the following variables interest rates economic activity stock returns and oil price volatility taking into account the structural break in the year 1986 we find a negative response of g7 stock markets to an increase in oil price volatility results also indicate that world oil price volatility is generally more significant for stock markets than the national oil price volatility

does the s p500 index lead the crude oil dynamics a complexity based approach abstract taking the complex property of nonlinear feedback connectivity into consideration the goal of this paper is to apprehend the interdependences between the financial and energy sectors our contribution is both theoretical and methodological we conduct a multivariate analysis employing nonlinear tools namely the partial transfer entropy and the asymmetric mackey glass causality test in particular we build a system comprising the petroleum complex crude oil gasoline and heating oil the s p500 index and the 1 month futures spot spread for crude oil by adopting a rolling window approach we observe a persistent lead lag relationship between the s p500 index and the market participants expectations for crude oil from 2004 to 2009 depending on the bubble period in the stock market it appears that the resulting coupling becomes subject to the deterioration of global economic activity induced by large common shocks

the inconsistency of consistent conjectures abstract conjectural variation models have been criticized because firms are right for the wrong reasons and because possible equilibria are abundant lately several papers have attempted to meet these difficulties by some condition of consistency or rationality on the conjectural variation this paper shows that stronger versions of such conditions lead into paradoxes while the weaker forms are of little use in solving the conceived problems the original cournot assumption actually satisfies consistency enterions the problems with consistent conjectures illuminates fundmental problems with too demanding information assumptions like perfect foresight such assumptions may create non trivial structures of self reference

the dependence structure across oil wheat and corn a wavelet based copula approach using implied volatility indexes abstract this paper examines the dependence structure between three commodities implied volatility indexes oil wheat and corn during bear normal and bull markets and at different scales for this purpose we combine wavelet and copula methods to analyse the changes of the tail dependence at different scales or investment horizons the results support evidence of time varying asymmetric tail dependence between the pair of cereals as well as between oil and the two cereals at different time horizons short term horizon medium term horizon and long term horizon suggesting that the dependence structure is sensitive to time horizons these results have important implications for the analysis of portfolio risk management

recent hikes in oil equity market correlations transitory or permanent this paper empirically examines the long run behavior of eight oil equity correlations based on the adcc asymmetric dynamic conditional correlation model and a novel decomposing approach we select equity price indexes from three developed countries the us the uk and germany and five brics member countries brazil russia india china and south africa and consider ten economic financial events for investigation seven correlations exhibit a positively sloped trend and one exhibits a horizontal trend all of these trends have undergone one or two structural breaks which moved the corresponding correlations to their highest ever evolutionary paths these structural breaks are associated with one or more of the ten episodes considered and a common event impacting all eight of the correlation trends is detected to be the 2008 adverse oil shock the broken trends explain why the correlations were low in the early years and high in the recent years our findings indicate that recent hikes in the oil equity correlations are a long run phenomenon

technological efficiency and the demand for energy road transport this paper reconsiders how far fuel efficiency induced by technological progress and presumably by high energy prices affects energy demand this investigation is motivated by one of the most important phenomenon of recent energy demand developments apparent asymmetry with respect to energy prices

wavelet based test of co movement and causality between oil and renewable energy stock prices abstract we studied co movement and causality between oil and renewable energy stock prices using continuous and discrete wavelets firstly to obtain information on dynamic correlations over time and for different time scales from wavelet coherence and secondly to obtain information on linear and non linear granger causality in the time frequency domain for general and sectoral renewable energy indices for the period 2006 2015 our findings indicate that dependence between oil and renewable energy returns in the short run was weak but gradually strengthened towards the long run mainly for the period 2008 2012 our causality tests provide evidence against linear causality at higher frequencies and in favour of unidirectional and bidirectional linear causality at lower frequencies in contrast we found consistent evidence of non linear causality running from renewable energy indices to oil prices at different time horizons and mixed evidence of causality running from oil to renewable energy prices these results have potential implications for investors in terms of hedging and for policymakers in terms of policy support decisions regarding the development of renewable energy

a wavelet analysis of mean and volatility spillovers between oil and brics stock markets this paper investigates the spillover effects of volatility and shocks between oil prices and the brics stock markets using multivariate approach and wavelet analysis at different time horizons hence we combine a multivariate arma garch model and wavelet multiresolution analysis to study this phenomenon a bivariate arma 1 1 garch 1 1 cdcc student t model was joined with modwt filter to capture a broad range of possible spillover effects in mean and variances of level prices at various time horizons generally empirical results provide strong evidence of time varying volatility in all markets under study however our proposed approach shows that oil price and stock market prices are directly affected by their own news and volatilities and indirectly affected by the volatilities of other prices and wavelet scale the results show also that mean and volatility spillover effects was decomposed into many sub spillovers on different time scales according to heterogeneous investors and market participants the practical implications of this study are critical innovative and useful for the local and international investors and also for the portfolio managers they can utilize this study to formulate the optimal oil bricks stock portfolios as well as lead to more accurate predictions of volatility spillovers patterns also in developing their hedging strategies

investigating dynamic multifirm market interactions in price and advertising diagnosing the nature and magnitu de of competitive interactions among firms is important for developing effective marketing strategies in this paper we formulate a game theoretic model of firm interaction to analyze the dynamic price and advertising competition among firms in a given p roduct market firm or brand level demand functions account for the contemporaneous and carry over effects of these marketing activities and also allow for the effects of competitor actions firms take into consideration the actions of their rivals as well as their own demand and cost functions both production and advertising when determining the profit maximizing price and advertising levels our formulation enables us to quantify not only the direction and magnitude of competitive reactions but also to identify the underlying form of market conduct that generates the particular pattern of interaction we specify and estimate a fully structural econometric model for three firms constituting a distinct sub market within a personal care product category we estimate the demand and competitive interaction parameters as well as the production and advertising cost functions for each firm we then derive implications for competitive interactions and market structure interestingly we find that while firms seem to compete on advertising they price cooperatively thereby enhancing their price cost margins

this is what happened to the oil price macroeconomy relationship abstract many of the quarterly oil price increases observed since 1985 are corrections to even bigger oil price decreases the previous quarter when one looks at the net increase in oil prices over the year recent data are consistent with the historical correlation between oil shocks and recessions

crude oil and stock markets causal relationships in tails abstract this paper considers the causal relationships between wti and dubai crude oil returns and five stock index returns s p 500 nikkei hang seng shanghai and kospi within the quantile causality framework by using daily data for a period from january 1 1996 to october 12 2012 the quantile causality test is useful for a comprehensive understanding of the causal relationship between two returns the test reveals several noteworthy results first although wti returns are not closely related to asian countries some financial markets such as nikkei and hang seng granger cause wti returns second the significance of causality from one market to another derives only from lower and upper levels of quantiles except for the case of causality from nikkei to wti returns third all stock index returns granger cause dubai crude oil returns over almost all quantile levels except for shanghai returns fourth dubai crude oil returns granger cause all asian stock index returns except for s p 500 returns finally the results indicate asymmetric causality from dubai crude oil returns to shanghai returns and kospi returns to dubai crude oil returns

measuring financial asset return and volatility spillovers with application to global equity markets we provide a simple and intuitive measure of interdependence of asset returns and or volatilities in particular we formulate and examine precise and separate measures of return spillovers and volatility spillovers our framework facilitates study of both non crisis and crisis episodes including trends and bursts in spillovers and both turn out to be empirically important in particular in an analysis of sixteen global equity markets from the early 1990s to the present we find striking evidence of divergent behavior in the dynamics of return spillovers vs volatility spillovers return spillovers display a gently increasing trend but no bursts whereas volatility spillovers display no trend but clear bursts

crude oil and stock markets stability instability and bubbles abstract we analyze the long run relationship between the world price of crude oil and international stock markets over 1971 1 2008 3 using a cointegrated vector error correction model with additional regressors allowing for endogenously identified breaks in the cointegrating and error correction matrices we find evidence for breaks after 1980 5 1988 1 and 1999 9 there is a clear long run relationship between these series for six oecd countries for 1971 1 1980 5 and 1988 2 1999 9 suggesting that stock market indices respond negatively to increases in the oil price in the long run during 1980 6 1988 1 we find relationships that are not statistically significantly different from either zero or from the relationships of the previous period the expected negative long run relationship appears to disintegrate after 1999 9 this finding supports a conjecture of change in the relationship between real oil price and real stock prices in the last decade compared to earlier years which may suggest the presence of several stock market bubbles and or oil price bubbles since the turn of the century

entry barriers and multiproduct oligopolies do they forebear or spoil abstract we provide a flexible method to test for a variety of multiproduct oligopolistic models and to estimate the relevance of entry conditions on industrial conduct we find that for the case of the uruguayan banking sector during the late 1970s multiproduct oligopolistic interactions were present however the partial relaxation of legal entry barriers substantially removed the multiproduct nature of these interactions

correlations and volatility spillovers between oil prices and the stock prices of clean energy and technology companies abstract in this paper multivariate garch models are used to model conditional correlations and to analyze the volatility spillovers between oil prices and the stock prices of clean energy companies and technology companies four different multivariate garch models bekk diagonal constant conditional correlation and dynamic conditional correlation are compared and contrasted the dynamic conditional correlation model is found to fit the data the best and generates results showing that the stock prices of clean energy companies correlate more highly with technology stock prices than with oil prices on average a 1 long position in clean energy companies can be hedged for 20 cents with a short position in the crude oil futures market

analyzing time varying volatility spillovers between the crude oil markets using a new method abstract the spillover effect is an important factor affecting the volatility of crude oil price basing on the study of diebold and yilmaz 2009 2012 2014 we propose a new method that calculates the time varying volatility spillover indexes by the generalized forecast error variance decomposition of tvp var sv model then using the new method we study the time varying volatility spillovers between four major crude oil markets wti brent oman tapis from november 29 2002 to july 13 2018 by comparing the results of our new method and traditional rolling window method we verify the superiority of our new method the results show that the volatility spillovers calculated by the new method are clearer more stable and not outlier sensitive from the estimated results of time varying volatility spillovers we find that the volatility spillover between crude oil markets is slowly increasing but there are obvious cyclical changes and from the correlation analysis and the granger causality test we find that the volatility and volatility spillovers are positively correlated and are two way granger causality which supported for the market infection hypothesis of king and wadhwani 1990

hedging emerging market stock prices with oil gold vix and bonds a comparison between dcc adcc and go garch while much research uses multivariate garch to model volatility dynamics and risk measures one particular type of multivariate garch model go garch has been underutilized this paper uses dcc adcc and go garch to model volatilities and conditional correlations between emerging market stock prices oil prices vix gold prices and bond prices a rolling window analysis is used to construct out of sample one step ahead forecasts of dynamic conditional correlations and optimal hedge ratios in most of the situations we study oil is the best asset to hedge emerging market stock prices hedge ratios from the adcc model are preferred most effective for hedging emerging market stock prices with oil vix or bonds hedge ratios estimated from the go garch are most effective for hedging emerging market stock prices with gold in some instances these results are reasonably robust to choice of model refits forecast length and distributional assumptions

the relationships between petroleum and stock returns an asymmetric dynamic equi correlation approach in this paper we propose an asymmetric dynamic equi correlation adeco model to investigate the correlations between returns of petroleum futures and stock indices our adeco reveals the in sample significant asymmetric effect in oil stock correlations to evaluate out of sample performance we consider a portfolio with petroleum futures and stocks in which the weights are determined by forecasts of covariance matrix we find that adeco provides portfolios with better performances than existing popular deco dcc and adcc models in the minimum variance framework moreover energy price risk can be better hedged by stocks in oil exporting countries than stocks in oil importing countries our findings are further demonstrated to be robust to the change of futures maturity

oil volatility oil and gas firms and portfolio diversification abstract this paper investigates the volatility spillovers and co movements among oil prices and stock prices of major oil and gas corporations over the period between 18th june 2001 and 1st february 2016 to do so we use the spillover index approach by diebold and yilmaz 2009 2012 2014 2015 and the dynamic correlation coefficient model of engle 2002 so as to identify the transmission mechanisms of volatility shocks and the contagion of volatility among oil prices and stock prices of oil and gas companies respectively given that volatility transmission across oil and major oil and gas corporations is important for portfolio diversification and risk management we also examine optimal weights and hedge ratios among the aforementioned series our results point to the existence of significant volatility spillover effects among oil and oil and gas companies stock volatility however the spillover is usually unidirectional from oil and gas companies stock volatility to oil volatility with bp chevron exxon shell and total being the major net transmitters of volatility to oil markets conditional correlations are positive and time varying with those between each of the aforementioned companies and oil being the highest finally the diversification benefits and hedging effectiveness based on our results are discussed

an empirical investigation of advertising strategies in a dynamic duopoly the equilibrium profit maximizing advertising policies of firms operating in a dynamic duopoly are derived by linking in a single framework the econometric estimation of the market response function and the technique of differential games that characterizes dynamic competitive behavior we use the lanchester model of combat to represent the system dynamics that capture the competitive shifts due to investments in advertising by the two market rivals we determine the equilibrium advertising levels using both closed and open loop policies we also compare these equilibrium advertising policies for each firm to those obtained using an optimal control theory formulation wherein the advertising spending levels of the rival are assumed to be known the empirical results obtained by analyzing the advertising rivalry between coke and pepsi for the period 1968 1981 under the above three alternative spending policies provide some interesting insights into the nature of competition between these two market rivals a significant contribution of this paper is to extend the existing literature on advertising competition by integrating theoretical and empirical analyses

islamic stocks conventional stocks and crude oil directional volatility spillover analysis in brics abstract this paper uses threshold garch tgarch and generalised forecast error variance decomposition to compute time domain and frequency domain volatility spillover the spillover technique is then applied to islamic and conventional stock indices and crude oil in brics countries brazil russia india china and south africa thus informing investors about the magnitude and speed of the volatility spillover we find that the total volatility spillover is driven mainly by a long term component accordingly these assets are suitable for investors with short and medium term investment horizons however analysis reveals that volatility spillover magnitude and speed increase substantially during the global financial crisis suggesting that investors in brazil russia and south africa with stocks in their portfolio should rebalance promptly dynamic covariance analysis shows that covariance between islamic and conventional stock index returns is the highest and exhibit a significant increase during the crisis period

asymmetric impact of oil price on islamic sectoral stocks abstract this paper extends the literature concerning non linearity in oil stock relationships by putting forward a new paradigm of sectoral and islamic elements we explore the asymmetric impact of oil price on islamic stocks from a sectoral perspective using non linear autoregressive distributed lag cointegration methodology the main advantage of this methodology relies on its ability to simultaneously capture the short and long run asymmetries through both positive and negative oil price shocks our results show weak linkages between oil price changes and the islamic composite index however the nature and sensitivity of the reaction of stock prices to oil price shocks vary considerably across different sectors in the longer horizon the relationships between oil price and many islamic sectoral stocks tend to follow a nonlinear pattern furthermore the behavior of the real economic sectors indices reflects the performance of the composite index that is oil price resistant during the turbulent period after 2008 the response of the sectoral indices to oil price movements witnessed notable changes where the sectoral gains from oil price drop that have been observed during the period of study have been found to diminish after 2008 our finding is in line with the argument that the islamic composite index is grounded more on and within the real sectors these findings are robust when considering different oil proxies and different data time frequencies

caviar conditional autoregressive value at risk by regression quantiles value at risk var has become the standard measure of market risk employed by financial institutions for both internal and regulatory purposes var is defined as the value that a portfolio will lose with a given probability over a certain time horizon usually one or ten days despite its conceptual simplicity its measurement is a very challenging statistical problem and none of the methodologies developed so far give satisfactory solutions interpreting the var as the quantile of future portfolio values conditional on current information we propose a new approach to quantile estimation which does not require any of the extreme assumptions invoked by existing methodologies such as normality or i i d returns the conditional autoregressive value at risk or caviar model moves the focus of attention from the distribution of returns directly to the behavior of the quantile we specify the evolution of the quantile over time using a special type of autoregressive process and use the regression quantile framework introduced by koenker and bassett to determine the unknown parameters since the objective function is not differentiable we use a differential evolutionary genetic algorithm for the numerical optimization utilizing the criterion that each period the probability of exceeding the var must be independent of all the past information we introduce a new test of model adequacy the dynamic quantile test applications to simulated and real data provide empirical support to this methodology and illustrate the ability of these algorithms to adapt to new risk environments

oil and the macroeconomy when prices go up and down an extension of hamilton s results in an important paper hamilton 1983 demonstrated a strong correlation between oil price changes and gross national product growth in u s data however his study pertained to a period in which all the large oil price movements were upward and thus it left unanswered the question whether the correlation persists in periods of price decline moreover the price variable he used was somewhat distorted by price controls in the 1970s this note investigates whether hamilton s results continue to hold when the sample is extended to include the recent oil market collapse and the oil price variable is corrected for the effects of price controls particular attention is given to the possibility of asymmetric responses to oil price increases and decreases as suggested in the structural employment literature loungani 1986 davis 1987 hamilton 1988 like hamilton i based my investigation on the gnp equation in sims s 1 980b six variable quarterly vector autoregressive model