Benoit Mandelbrot, mathématicien et savant multidisciplinaire, s'intéressa très tôt dans sa carrière à l'étude statistique des données économiques et financières et fut à l'origine de nombreuses idées importantes dans la modélisation statistique des risques financiers, sujet qui le...

We apply several recently proposed tests for structural breaks in conditional variance and covariance dynamics. The tests apply to both the class of ARCH and SV type processes and allow for long memory features. We also apply them to data-driven volatility estimators using high-frequency data...

We identify and examine the presence of the long memory in equity returns and more generally in specific transformations of these returns, on both the US and European stock markets. Taking into account the persistence phenomenon, we analyze the effect of the splitting of the sample period on the...