Special session of the European Seminar for the Academic year 2010-2011
lundi 28 mars 2011, 15h00 - 18h00
15h Antoine Chambaz (Université Paris Descartes)
« Modèles de régression seuillée adaptés aux études cas-témoins, et le risque de cancer du poumon dû à des expositions professionnelles à l’amiante en France. »
Asbestos has been known for many years as a powerful carcinogen. Our purpose is quantify the relationship between an occupational exposure to asbestos and an increase of the risk of lung cancer. Furthermore, we wish to tackle the very delicate question of the evaluation, in subjects suffering from a lung cancer, of how much the amount of exposure to asbestos explains the occurrence of the cancer. For this purpose, we rely on a recent French case-control study. We build a large collection of threshold regression models, data-adaptively select a better model in it by multi-fold likelihood-based cross-validation, then fit the resulting better model by maximum likelihood. A necessary preliminary step to eliminate the bias due to the case-control sampling design is made possible because the probability distribution of being a case can be computed beforehand based on an independent study. The implications of the fitted model in terms of a notion of maximum number of years of life guaranteed free of lung cancer are discussed.
Ceci est une collaboration avec C. Huber, D. Choudat, J-C. Pairon et M. J. van der Laan.
15h45 Nikolaos Limnios (UTC, LMAC, Compiègne)
« Random Evolutions in Semi-Markov Media and Estimation Problems »
We present random evolutions in semi-Markov media in discrete-time and their average and diffusion approximation. We present as an application some estimation problem. In particular an estimator of the stationary process functional of a semi-Markov chain is proposed and its asymptotic properties.
17h Ildar Ibragimov (Steklov Institute, Saint Petersbourg, Russie)
« Nonparametric estimation of the intensity density of Poisson processes. Asymptotic results. »
C. Huber – N. Limnios – M. Mesbah – M. Nikulin
PARIS Descartes UTC PARIS VI BORDEAUX 2