24 papers
On a conjecture of Lamkin and Tkocz: Log-convexity of moments of Bernoulli sample means
Frédéric Ouimet, Frédéric Ouimet
Let be independent random variables, and let . We prove that, for every real , the sequenc…
Log-convexity and log-concavity of noncentral gamma sums and differences
Robert E. Gaunt, Frédéric Ouimet
We study log-convexity and log-concavity of densities obtained from sums and differences of two independent noncentral gamma random variables. We give a complete classification of…
On Wilks' problem: Exact recursive formulas via Stein's method for the joint moments of disjoint principal minors of Wishart random matrices
Robert E. Gaunt, Frédéric Ouimet
In a 1934 Annals of Mathematics paper, Samuel S. Wilks posed the problem of computing joint moments of disjoint principal minors of Wishart random matrices, describing the general…
On the Dirichlet-kernel Gasser--Müller estimator and its competitors for fixed design regression on the simplex
Hanen Daayeb, Christian Genest, Salah Khardani +2
A Dirichlet-kernel Gasser-Müller (D-GM) estimator is introduced for fixed design regression on the simplex, extending the univariate analog due to Chen [Statist. Sinica, vol. 10(1…
Stein's method for the symmetric matrix normal distribution with an application to the approximation of the Wishart law
Robert E. Gaunt, Frédéric Ouimet
In this paper, we extend Stein's method to the symmetric matrix normal distribution. In particular, we obtain a Stein characterization of the symmetric matrix normal distribution i…
Dirichlet kernel density estimation on the simplex with missing data
Sami Baraket, Hanen Daayeb, Salah Khardani +2
Nonparametric density estimation for compositional data supported on the simplex is examined under a missing at random mechanism. Rather than imputing missing values and estimating…