the forecasting ability of correlations implied in foreign exchange options abstract this paper evaluates the forecasting accuracy of correlations derived from implied volatilities in dollar mark dollar yen and mark yen options from january 1989 to may 1995 as a forecast of realized correlation between the dollar mark and dollar yen implied correlation is compared against three alternative forecasts based on time series data historical correlation riskmetrics exponentially weighted moving average correlation and correlation estimated using a bivariate garch 1 1 model at the 1 month and 3 month forecast horizons we find that implied correlation outperforms often significantly these alternative forecasts in combinations implied correlation always incrementally improves the performance of other forecasts but not the converse in certain cases historically based forecasts contribute no incremental information to implied forecasts the superiority of the implied correlation forecast holds even when forecast errors are weighted by realized variances reflecting correlation s contribution to the dollar variance of a multicurrency portfolio

the term structure of volatility implied by foreign exchange options this paper illustrates regression and kalman filtering methods for estimating the time varying term structure of volatility expectations revealed by options prices short and long term expectations are estimated for four currencies using daily phlx options prices from 1985 to 1989 throughout this period there were important differences between shortand long term expectations the slope of the term structure changed frequently and there were significant variations in long term volatility expectations the expectation estimates can be used to value otc options to improve hedging strategies and to test the hypothesis that the options market overreacts

how important is the term structure in implied volatility surface modeling evidence from foreign exchange options we claim that previously proposed parametric specifications that linearly approximate the term structure of the implied volatility surface ivs in option prices fail to capture important information regarding the expectations of market participants this paper proposes a parametric specification for describing the ivs that allows flexible modeling of the term structure through a nelson and siegel 1987 factorization recently proposed by diebold and li 2006 in the context of yield curve modeling the specification is tested on implied volatilities from the over the counter foreign exchange options market where contracts with long expiries are actively traded and thus the term structure dimension of the surface should be very important we first show that the proposed volatility specification can consistently and remarkably improve our ability to describe the surface on any given day we then establish the economic relevance of the incremental information captured by our proposed specification by showing that it can produce more accurate forecasts of implied volatility that can support long term profitable trading strategies in the absence of transaction costs

the volatility risk premium embedded in currency options this study employs a non parametric approach to investigate the volatility risk premium in the over the counter currency option market using a large database of daily delta neutral straddle quotes in four major currencies the british pound the euro the japanese yen and the swiss franc we find that volatility risk is priced in all four currencies across different option maturities we find that the volatility risk premium is negative with the premium decreasing in maturity finally we also find evidence that jump risk may be priced in the currency option market

the informational content of implied volatility implied volatility is widely believed to be informationally superior to historical volatility because it is the markets forecast of future volatility but for s p 100 index options the most actively traded contract in the united states we find implied volatility in aggregate and across subsamples separated by maturity and strike price implied volatility has virtually no correlation with future volatility and it does not incorporate the information contained in recent observed volatility article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

using option prices to estimate realignment probabilities in the european monetary system the case of sterling mark abstract this paper describes a procedure for estimating the market s perceived probability distribution of future exchange rates from the prices of risk reversals strangles and other currency options and uses the procedure to estimate the risk neutral ex ante probability of a realignment of the pound sterling the procedure for estimating the realignment probabilities relies on the jump diffusion model of exchange rate behavior and the resulting option pricing formula by fitting this model to market option price data i retrieve the unobserved parameters of the jump diffusion process i then use these parameter estimates to estimate the ex ante probability distribution of exchange rates and thus the realignment probabilities

arbitrage based tests of target zone credibility evidence from erm cross rate options this paper introduces two arbitrage based tests of target zone credibility using a new data source exchange rate mechanism cross rate options using daily option prices from september 1991 to august 1994 the authors assess the credibility of the pound mark and mark lira target zones that collapsed in september 1992 and the ongoing mark french franc target zone these tests are based on restrictions that must apply to all option prices within a credible target zone and are free from specification error and estimation error the authors also identify a minimum intensity of realignment an expression indicating the probability weighted average realignment size copyright 1996 by american economic association

elephant poaching ivory trafficking problems in sub saharan africa an application of o hara s principles of political economy this paper examines the complex social problem of african elephant decimation using a political economy approach this paper applies five principles of o hara s political economy pope historical specificity circular and cumulative causation uneven development heterogeneous agents and contradiction pope provides a practical tool for scrutinising the interdependent aspects of a problem the culture of conspicuous consumption for ivory is a key historical driver of demand yet a core integrated factor that helps explain the current crisis relates to the principle of uneven development the role of uneven development can be indirect through lack of human development causing high crime and corruption rates weak policy frameworks and conflicts in land ownership further heterogeneity of agents adds to the complexity of the networks engaged in the decimation of elephants linked to the poaching trafficking circuit of heterogeneous agents this paper identifies two specific elephant contradictions between the market forces of durable fixed capital and environment elephant capital this study contributes to the literature by analysing the interlinking cumulative processes of elephant poaching and ivory trafficking networks which previous studies in the economics literature tend to ignore

heterogeneity in risky choice behaviour in a broad population we analyse risk preferences using an experiment with real incentives in a representative sample of 1 422 dutch respondents our econometric model incorporates four structural parameters that vary with observed and unobserved characteristics utility curvature loss aversion preferences towards the timing of uncertainty resolution and the propensity to choose randomly rather than on the basis of preferences we find that all four parameters contribute to explaining choice behaviour the structural parameters are significantly associated with socio economic variables but it is essential to incorporate unobserved heterogeneity in each of them to match the rich variety of choice patterns in the data

forecasting stock return variance toward an understanding of stochastic implied volatilities we examine the behavior of measured variances from the options market and the underlying stock market under the joint hypotheses that markets are informationally efficient and that option prices are explained by a particular asset pricing model forecasts from time series models of the stockreturn process should not have predictive content given the market forecast as embodied in option prices both in sample and out of sample tests suggest that this hypothesis can be rejected using simulations we show that biases inherent in the procedure we use to imply variances cannot explain this result thus we provide evidence inconsistent with the orthogonality restrictions of option pricing models that assume that variance risk is unpriced these results also have implicationsfor optimal variance forecast rules

predicting volatility in the foreign exchange market measures of volatility implied in option prices are widely believed to be the best available volatility forecasts in this article we examine the information content and predictive power of implied standard deviations isds derived from chicago mercantile exchange options on foreign currency futures the article finds that statistical time series models even when given the advantage of ex post parameter estimates are outperformed by isds isds however also appear to be biased volatility forecasts using simulations to investigate the robustness of these results the article finds that measurement errors and statistical problems can substantially distort inferences even accounting for these however isds appear to be too variable relative to future volatility it is widely believed that the volatility implied in option prices is the market s best estimate of future volatility after all if it were not one could devise a trading strategy that could generate profits by identifying mispriced options the purpose of this article is to investigate the information content and predictive power of volatility implied in options on foreign currencies the paper focuses on options on currency futures traded on the chicago mercantile exchange cme because of the depth and liquidity of cme futures and options traded side by side in the same market implied standard deviations isds allow for clean tests of the predictive power of implied volatilities early studies of the information content of isds have generally found that these contain substantial information for future volatility latane and rendleman 1976 chiras and manaster 1978 and beckers 1981 for example regress future volatility on the weighted implied volatility across a broad sample of chicago board options exchange cboe stocks and find that options contain volatility forecasts that are more accurate than historical measures 1 these studies performed shortly after the 1973 beginning of the cboe option market could only use a relatively short time span and therefore focused on cross sections rather than time series predictions

recovering an asset s implied pdf from option prices an application to crude oil during the gulf crisis we develop a general method for estimating the implied martingale equivalent probability density function pdf for futures prices from american options prices the early exercise feature of american options precludes expressing the price of the option in terms of the pdf there exist tight bounds for the price of american options in terms of the pdf we demonstrate how these bounds together with observed option prices can be used to estimate the parameters of the pdf we estimate the distribution for crude oil during the persian gulf crisis and find the distribution differs significantly from that recovered using standard techniques

predictable dynamics in implied volatility surfaces from otc currency options recent empirical studies report predictable dynamics in the volatility surfaces that are implied by observed index option prices such as those prescribed by general equilibrium models using an extensive data set from the over the counter options market we document similar predictability in the factors that capture the daily variation of surfaces implied by options on 25 different foreign exchange rates we proceed to demonstrate that simple vector autoregressive specifications for the factors can help produce accurate out of sample forecasts of the systematic component of the surface at short horizons profitable delta hedged positions can be set up based on these forecasts however profits disappear when typical transaction costs are taken into account and when trading rules on wide segments of the surface are sought

a utility based comparison of some models of exchange rate volatility abstract when estimates of variances are used to make asset allocation decisions underestimates of population variances lead to lower expected utility than equivalent overestimates a utility based criterion is asymmetric unlike standard criteria such as mean squared error to illustrate how to estimate a utility based criterion we use five bilateral weekly dollar exchange rates 1973 1989 and the corresponding pair of eurodeposit rates of homoskedastic garch autoregressive and non parametric models for the conditional variance of each exchange rate garch models tend to produce the highest utility on average a mean squared error criterion also favors garch but not as sharply

the predictive power of the implied volatility of options traded otc and on exchanges abstract this paper investigates the efficiency of stock index options traded over the counter otc and on the exchanges in hong kong and japan our findings suggest that implied volatility is superior to either historical volatility or a garch type volatility forecast in predicting future volatility in both the otc and exchange markets this paper is also one of the first to compare the predictive power of the implied volatility of stock index options traded otc to that of exchange traded stock index options our evidence suggests that the otc market is more efficient than the exchanges in japan but that the opposite is true in hong kong

the performance of alternative valuation models in the otc currency options market abstract we compare option valuation models based on regime switching garch and jump diffusion processes to a standard smile model in which black and scholes 1973 implied volatilities are allowed to vary across strike prices the regime switching garch and jump diffusion models provide significant improvement over a fixed smile model in fitting gbp and jpy option prices both in sample and out of sample the jump diffusion model achieves the tightest fit a time varying smile model however provides hedging performance that is comparable to the other models for the gbp options this result suggests that standard option valuation techniques may provide a reasonable basis for trading and hedging strategies

forecasting the comovements of spot interest rates abstract time varying covariance models are compared in the french and german interest rate markets of the pre euro period a bivariate asymmetric dynamic covariance model with level effect best characterizes the in sample variance covariance dynamics model comparison using economic loss functions raises some doubts with alternative models performing similarly out of sample results show that the variance covariance matrix is best forecasted using a vech model with level effect but no volatility spillover not entirely confirming the in sample evidence simple models using exponentially weighted moving averages of past observations perform similarly to the best bivariate model thus some features required to obtain a good in sample fit do not have additional out of sample forecasting power due to overfitting

modeling heteroscedasticity in daily foreign exchange rates this article estimates autoregressive conditionally heteroscedastic arch and generalized arch garch models for five foreign currencies using 10 years of daily data a variety of arch and garch specifications a number of nonnormal error densities and a comprehensive set of diagnostic checks it finds that arch and garch models can usually remove all heteroscedasticity in price changes in all five currencies goodness of fit diagnostics indicate that exponential garch with certain nonnormal distributions fits the canadian dollar extremely well and the swiss franc and the deutsche mark reasonably well only one nonnormal distribution fits the japanese yen reasonably well none fit the british pound

preferences inflation and welfare abstract this paper systematically examines how degrees of household risk aversion ra and elasticity of intertemporal substitution eis impact the welfare costs of inflation in a heterogeneous agent environment featuring capital and essential money empirical evidence suggests that households have degrees of ra and eis that differ on average from traditional values and display large amounts of dispersion capturing these empirical features of preference values in an otherwise standard model leads to welfare enhancements of inflation due to household substitution of money for capital the analysis also compares the welfare implications for alternative ways to implement monetary policy

the road less travelled institutional aspects of data and their influence on empirical estimates with an application to tests of forward rate unbiasedness the difference between data used in empirical studies and that envisioned in the theory can influence empirical estimates sometimes by enough that the direction of future research is altered this paper illustrates how in the context of tests of forward rate unbiasedness a lack of articulation about the mechanics underlying foreign exchange market speculation and about the institutional aspects governing spot and forward rate contracts leads to sampling of the data in a way that is not consistent with the theory the authors find that the sampling problems account for some but not all of the bias in the coefficient on the forward premium copyright 1996 by royal economic society

stability and forecasting of the comovement measures of international stock market returns abstract the potential benefits to international diversification may be less if the comovement structure of international equity returns is non stationary than if it is this paper examines the intertemporal stability of the correlation and the covariance structure of the returns of ten major stock markets whilst empirical evidence supports the hypothesis that the correlation structure is stable over time the empirical support for the stability of the covariance matrix is much weaker alternative forecasting models of the comovement structure are examined

standard deviations implied in option prices as predictors of future stock price variability abstract standard deviations implied in option prices have recently been introduced as being better than average predictors of future stock price variability this article specifically studies the predictive ability of implicit standard deviations taking into account the dividend problem and the problem of optimal weighting schemes of the standard deviations when there are several options on the same stock transaction data information was used to study the importance of non simultaneities in observing stock and option prices