Laurent

Publications

Robust forecasting of dynamic conditional correlation GARCH modelsJournal articleKris Boudt, Jón Danielsson et Sébastien Laurent, International Journal of Forecasting, Volume 29, Issue 2, pp. 244-257, 2013

Large one-off events cause large changes in prices, but may not affect the volatility and correlation dynamics as much as smaller events. In such cases, standard volatility models may deliver biased covariance forecasts. We propose a multivariate volatility forecasting model that is accurate in the presence of large one-off events. The model is an extension of the dynamic conditional correlation (DCC) model. In our empirical application to forecasting the covariance matrix of the daily EUR/USD and Yen/USD return series, we find that our method produces more precise out-of-sample covariance forecasts than the DCC model. Furthermore, when used in portfolio allocation, it leads to portfolios with similar return characteristics but lower turnovers, and hence higher profits.

On loss functions and ranking forecasting performances of multivariate volatility modelsJournal articleSébastien Laurent, Jeroen V. K. Rombouts et Francesco Violante, Journal of Econometrics, Volume 173, Issue 1, pp. 1-10, 2013

The ranking of multivariate volatility models is inherently problematic because when the unobservable volatility is substituted by a proxy, the ordering implied by a loss function may be biased with respect to the intended one. We point out that the size of the distortion is strictly tied to the level of the accuracy of the volatility proxy. We propose a generalized necessary and sufficient functional form for a class of non-metric distance measures of the Bregman type which ensure consistency of the ordering when the target is observed with noise. An application to three foreign exchange rates is provided.

Nonparametric Tests for Intraday Jumps: Impact of Periodicity and Microstructure NoiseBook chapterKris Boudt, Jonathan Cornelissen, Christophe Croux et Sébastien Laurent, In: Handbook of Volatility Models and Their Applications, Luc Bauwens, Christian M. Hafner et Sébastien Laurent (Eds.), 2012-04, Volume 18, pp. 447-463, John Wiley & Sons, Inc., 2012

This chapter contains sections titled: * Introduction * Model * Price Jump Detection Method * Simulation Study * Comparison on NYSE Stock Prices * Conclusion

Nonparametric Tests for Intraday Jumps: Impact of Periodicity and Microstructure NoiseBook chapterKris Boudt, Jonathan Cornelissen, Christophe Croux et Sébastien Laurent, In: Handbook of Volatility Models and Their Applications, Luc Bauwens, Christian M. Hafner et Sébastien Laurent (Eds.), 2012-04, Volume 18, pp. 447-463, John Wiley & Sons, Inc., 2012

This chapter contains sections titled: * Introduction * Model * Price Jump Detection Method * Simulation Study * Comparison on NYSE Stock Prices * Conclusion

Handbook of Volatility Models and Their ApplicationsBookLuc Bauwens, Christian M. Hafner et Sébastien Laurent (Eds.), 2012-04, 566 pages, John Wiley & Sons, 2012

A complete guide to the theory and practice of volatility models in financial engineering Volatility has become a hot topic in this era of instant communications, spawning a great deal of research in empirical finance and time series econometrics. Providing an overview of the most recent advances, Handbook of Volatility Models and Their Applications explores key concepts and topics essential for modeling the volatility of financial time series, both univariate and multivariate, parametric and non-parametric, high-frequency and low-frequency. Featuring contributions from international experts in the field, the book features numerous examples and applications from real-world projects and cutting-edge research, showing step by step how to use various methods accurately and efficiently when assessing volatility rates. Following a comprehensive introduction to the topic, readers are provided with three distinct sections that unify the statistical and practical aspects of volatility: Autoregressive Conditional Heteroskedasticity and Stochastic Volatility presents ARCH and stochastic volatility models, with a focus on recent research topics including mean, volatility, and skewness spillovers in equity markets Other Models and Methods presents alternative approaches, such as multiplicative error models, nonparametric and semi-parametric models, and copula-based models of (co)volatilities Realized Volatility explores issues of the measurement of volatility by realized variances and covariances, guiding readers on how to successfully model and forecast these measures Handbook of Volatility Models and Their Applications is an essential reference for academics and practitioners in finance, business, and econometrics who work with volatility models in their everyday work. The book also serves as a supplement for courses on risk management and volatility at the upper-undergraduate and graduate levels.

Volatility forecasts evaluation and comparisonJournal articleSébastien Laurent et Francesco Violante, Wiley Interdisciplinary Reviews: Computational Statistics, Volume 4, Issue 1, pp. 1-12, 2012

This article surveys the most important developments in volatility forecast comparison and model selection. We review a number of evaluation methods and testing procedures for predictive accuracy based on statistical loss functions. We also review recent contributions on the admissible form of loss functions ensuring consistency of the ordering when forecast performances are evaluated with respect to an imperfect volatility proxy. The techniques discussed are illustrated using artificial and EUR/USD exchange rate data. WIREs Comp Stat 2012, 4:1–12. doi: 10.1002/wics.190For further resources related to this article, please visit the WIREs website

Testing conditional asymmetry: A residual-based approachJournal articleSébastien Laurent, Philippe Lambert et David Veredas, Journal of Economic Dynamics and Control, Volume 36, Issue 8, pp. 1229-1247, 2012

We propose three residual-based tests for conditional asymmetry. The distribution is assumed to fall into the class of skewed distributions of Fernández and Steel (1998). In this class, asymmetry is measured by the ratio between the probabilities of being larger and smaller than the mode. Estimation is performed under the null hypothesis of constant asymmetry of the innovations and, in a second step, tests for conditional asymmetry are performed on generalized residuals through parametric and nonparametric methods. We derive the asymptotic distribution of the tests that incorporates the uncertainty of the estimated parameters. A Monte Carlo study shows that neglecting this uncertainty severely biases the tests. An empirical application on a basket of daily returns reveals that financial data often present dynamics in the conditional skewness.

Do jumps mislead the FX market?Journal articleSébastien Laurent, Jean-Yves Gnabo, Jérôme Lahaye et Christelle Lecourt, Quantitative Finance, Volume 12, Issue 10, pp. 1521-1532, 2012

This paper investigates the link between jumps in the exchange rate process and rumours of central bank interventions. Using the case of Japan, we analyse specifically whether jumps trigger false reports of intervention (i.e. an intervention is reported when it did not occur). Intraday jumps are extracted using a non-parametric technique recently proposed by Lee and Mykland in 2008 and by Andersen et al . in 2007, and later modified by Boudt et al . in 2011. Rumours are identified by using a unique database of Reuters and Dow Jones newswires. Our results suggest that a significant number of jumps on the YEN/USD have been falsely interpreted by the market as being the result of a central bank intervention. The paper has policy implications in terms of central bank interventions. We show that in times where the central bank is known to intervene, some investors may attach a lot of weight to central bank interventions as a source of exchange rate movement, leading to a false ‘intervention explanation’ for observed jumps.

On the forecasting accuracy of multivariate GARCH modelsJournal articleSébastien Laurent, Jeroen V. K. Rombouts et Francesco Violante, Journal of Applied Econometrics, Volume 27, Issue 6, pp. 934-955, 2012

This paper addresses the question of the selection of multivariate GARCH models in terms of variance matrix forecasting accuracy with a particular focus on relatively large scale problems. We consider 10 assets from NYSE and NASDAQ and compare 125 model based one-step-ahead conditional variance forecasts over a period of 10 years using the model confidence set (MCS) and the Superior Predictive Ability (SPA) tests. Model performances are evaluated using four statistical loss functions which account for different types and degrees of asymmetry with respect to over/under predictions. When considering the full sample, MCS results are strongly driven by short periods of high market instability during which multivariate GARCH models appear to be inaccurate. Over relatively unstable periods, i.e. dot-com bubble, the set of superior models is composed of more sophisticated specifications such as orthogonal and dynamic conditional correlation (DCC), both with leverage effect in the conditional variances. However, unlike the DCC models, our results show that the orthogonal specifications tend to underestimate the conditional variance. Over calm periods, a simple assumption like constant conditional correlation and symmetry in the conditional variances cannot be rejected. Finally, during the 2007-2008 financial crisis, accounting for non-stationarity in the conditional variance process generates superior forecasts. The SPA test suggests that, independently from the period, the best models do not provide significantly better forecasts than the DCC model of Engle (2002) with leverage in the conditional variances of the returns.

Outlyingness Weighted CovariationJournal articleSébastien Laurent et Christophe Croux, Journal of Financial Econometrics, Volume 9, Issue 4, pp. 657-684, 2011

Quadratic covariation is a popular descriptive measure for the volatility of a multivariate price process. It is consistently estimated by the sum of outer products of high-frequency returns. The proposed realized outlyingness weighted covariation (ROWCov) is a weighted sum of outer products of high-frequency returns and downweights returns that, because of jumps or other reasons, are outliers under the Brownian semimartingale model. The ROWCov is positive semidefinite and remains consistent for the integrated covariance in the presence of a finite-activity jump process. We illustrate the usefulness of the estimator on five-minute returns on the transaction prices of the Dow Jones Industrial Average constituents. Copyright The Author 2011. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com., Oxford University Press.