Séance Séminaire

Séminaire de Probabilités et Statistique

lundi 10 octobre 2022 à 13:45 - UM - Bât 09 - Salle de conférence (1er étage)

Julien Chiquet (MIA Paris, Université Paris-Saclay, AgroParisTech, INRAE)

[ANNULÉ] Variational Inference in the Poisson-Lognormal Model: optimisation and estimation [Séminaire KIM]

The multivariate Poisson-lognormal (PLN) model is a popular latent variable model commonly used to describe abundance tables, which relies on a Gaussian latent layer to encode the dependencies between count-valued variables in a covariance matrix. It can be viewed as a multivariate mixed Poisson regression model. The PLN model turns out to be a versatile framework, within which a variety of analyses can be performed, including multivariate sample comparison, clustering of sites or samples, dimension reduction (ordination) for visualization purposes, or inferring interaction networks. Inferring such models raises both statistical and computational issues, many of which were solved in recent contributions using variational techniques and convex optimization tools. I will presents the general PLN framework and I will describe some recent advances in variational optimization of such models and the statistical properties of the associated estimators.

Séminaire à 13h45 en salle 109 (IMAG, bâtiment 9).
Également retransmis sur zoom : https://umontpellier-fr.zoom.us/j/94087408185