Date/heure
31 mai 2018
09:15 - 10:15
Oratrice ou orateur
Jean Marc Freyermuth
Catégorie d'évènement Groupe de travail Probabilités et Statistique
Résumé
Sophisticated functional connections appears in experiments designed for assessing the visual working memory of the human brain. Elucidating the nature
of these interactions is supposedly a doorway for fruitful inference on brain cognitive processes. A challenging aspect is that they may involve brain waves
oscillatory components of possibly different frequencies. We develop a statistical methodology to study collections of replicated spatially localized EEG time
series. In the pursue of realistic and tractable time series models, we introduce
a new class of spatio-temporal processes that are time-harmonizable. We consider available replicates and seek for the estimation of both the spatial Loeve-
spectrum and the spatial dual-frequency coherence function. In other words we
measure a squared correlation coefficient across different frequencies between
any spatial locations. Our method exploit the spatial correlations to improve
the local estimation of the coherence between different frequency bands. We
derive the asymptotic distribution of the spatial coherence function and build
bootstrap-based confidence intervals.
This is based on joint work with John Aston, Dominique Dehay, Anna Dudek
and Denes Scusz.