A concentration approach to sensitivity studies in statistical estimation problems

It is shown that the concept of concentration is of potential interest in the sensitivity study of some parameters and related estimators. Basic ideas are introduced for a real parameter θ>0 together with graphical representations using Lorenz curves of concentration. Examples based on the mean, standard deviation and variance are provided for some classical distributions. This concentration approach is also discussed in relation with influence functions. Special emphasis is given to the average concentration of an estimator which provides a sensitivity measure allowing one to compare several estimators of the same parameter. Properties of this measure are investigated through simulation studies and its practical interest is illustrated by examples based on the trimmed mean and the Winsorized variance.     

Projection Pursuit Through Relative Entropy Minimization

Projection Pursuit methodology permits to solve the difficult problem of finding an estimate of a density defined on a set of very large dimension. In his seminal article, “Projection Pursuit”, Huber (1985 Huber , P. ( 1985 ). Projection pursuit . The Annals of Statistics 13 ( 2 ): 435 – 525 With discussion .[Crossref], [Web of Science ®] , [Google Scholar]) evidenced the interest of the Projection Pursuit method thanks to the factorization of a density into a Gaussian component and some residual density in a context of Kullback–Leibler divergence maximisation.

In the present article, we introduce a new algorithm, and in particular, a test for the factorisation of a density estimated from an iid sample.     

Parenting,emotion regulation,and externalizing symptomatology as adolescent antecedents to young adult health risk behaviors

This study used longitudinal data to elucidate how trajectories of negative parenting across adolescence are associated with young adult health risk behaviors (HRBs) by testing difficulties with emotion regulation and externalizing symptomatology as sequential underlying mediators. The sample included 167 adolescents (53% males, M_age = 14 at Time 1 and M_age = 18 at Time 5) who were assessed five times. Adolescents self-reported on negative parenting, emotion regulation, externalizing symptomatology, and engagement in HRBs. Results suggest that increasingly negative parenting across adolescence has adverse consequences for emotion regulation development and in turn, externalizing symptomatology, which confers risk for young adult HRBs. Results offer insights towards mechanisms for prevention and intervention and public health policy aimed at reducing the prevalence and consequences of engagement in HRBs.