The method of moments proposed by Carrasco and Florens (2000) permits to fully exploit the information contained in the characteristic function and yields an estimator which is asymptotically as effi cient as the maximum likelihood estimator. However, this estimation procedure depends on a regularization or tuning parameter α that needs to be selected. The aim of the present paper is to provide...

We present a fully automated algorithm for tissue segmentation of noisy, low contrast magnetic resonance (MR) images of the brain. We use a mixture model composed of a large number of Gaussians to represent the brain image. Each tissue is represented by a large number of the Gaussian components in order to capture the complex tissue spatial layout. The intensity of a tissue is considered a glob...

Le CIRANO collabore avec de nombreux centres et chaires de recherche universitaires dont on peut consulter la liste sur son site web. Les cahiers de la série scientifique (CS) visent à rendre accessibles des résultats de recherche effectuée au CIRANO afin de susciter échanges et commentaires. Ces cahiers sont écrits dans le style des publications scientifiques. Les idées et les opinions émises ...

Introduction: Micrometeorites are that fraction of the extraterrestrial dust flux that survives atmospheric entry to be recovered from the Earth’s surface. The majority of large micrometeorites (>50 μm), recovered from Antarctic ice, experience significant heating during atmospheric entry with the result that volatilebearing phases, such as clay minerals, have thermally decomposed. A significan...