Exact calculations for false discovery proportion with application to least favorable configurations

In a context of multiple hypothesis testing, we provide several new exact calculations related to the false discovery proportion (FDP) of step-up and step-down procedures. For step-up procedures, we show that the number of erroneous rejections conditionally on the rejection number is simply a binomial variable, which leads to explicit computations of the c.d.f., the {$s$-th} moment and the mean of the FDP, the latter corresponding to the false discovery rate (FDR). For step-down procedures, we derive what is to our knowledge the first explicit formula for the FDR valid for any alternative c.d.f. of the $p$-values. We also derive explicit computations of the power for both step-up and step-down procedures. These formulas are "explicit" in the sense that they only involve the parameters of the model and the c.d.f. of the order statistics of i.i.d. uniform variables. The $p$-values are assumed either independent or coming from an equicorrelated multivariate normal model and an additional mixture model for the true/false hypotheses is used. This new approach is used to investigate new results which are of interest in their own right, related to least/most favorable configurations for the FDR and the variance of the FDP

A semiparametric extension of the stochastic block model for longitudinal networks

To model recurrent interaction events in continuous time, an extension of the stochastic block model is proposed where every individual belongs to a latent group and interactions between two individuals follow a conditional inhomogeneous Poisson process with intensity driven by the individuals' latent groups. The model is shown to be identifiable and its estimation is based on a semiparametric variational expectation-maximization algorithm. Two versions of the method are developed, using either a nonparametric histogram approach (with an adaptive choice of the partition size) or kernel intensity estimators. The number of latent groups can be selected by an integrated classification likelihood criterion. Finally, we demonstrate the performance of our procedure on synthetic experiments, analyse two datasets to illustrate the utility of our approach and comment on competing methods

Continuing the Metalation and Ring Closure of Biliazine

Continuing previous research conducted by Dr. Ziegler and his Graduate Students in which different metals were selected to metalate the compound Biliazine as well as finding metals that could be used to close the ring system in Biliazine

How Geometry Controls the Tearing of Adhesive Thin Films on Curved Surfaces

Flaps can be detached from a thin film glued on a solid substrate by tearing and peeling. For flat substrates, it has been shown that these flaps spontaneously narrow and collapse in pointy triangular shapes. Here we show that various shapes, triangular, elliptic, acuminate or spatulate, can be observed for the tears by adjusting the curvature of the substrate. From combined experiments and theoretical models, we show that the flap morphology is governed by simple geometric rules.Comment: 6 pages, 5 figure

Entre injonctions contradictoires et bricolages identitaires : quelles identifications pour les descendants d’immigrés marocains en Belgique ?

Cet article propose une grille d’analyse des processus identitaires qui se jouent chez les descendants d’immigrés marocains en Belgique, en regard des familles immigrées et du cadre social. Les descendants d’immigrés marocains se trouvent privés de l’identification pleine aux parents ainsi que de l’héritage d’une mémoire familiale et collective. Soumis à une injonction contradictoire de la part de leurs parents et de la société (« Réussissez, mais restez fidèles aux traditions »; « Intégrez-vous, mais vous serez toujours considérés comme des immigrés »), ils échappent difficilement aux processus sociaux d’assignation à une altérité identitaire dévalorisée et sont contraints de bricoler de nouvelles formes identitaires. Cette problématique identitaire est située dans le cadre plus large du déclin du mode traditionnel d’hériter et de la transmission généalogique dans la modernité. Mais le hiatus profond entre le contexte de socialisation des parents immigrés et celui de leurs enfants et l’impact de la domination sociale sont tels que les processus d’identification dans l’immigration marocaine sont particulièrement complexes.This article provides an analytic framework for understanding the identity processes, with respect to immigrant families and the social situation, that are at play among descendants of Moroccan immigrants in Belgium. They are deprived of the possibility of fully identifying with their parents and of inheriting a familial and collective memory. Receiving contradictory instructions from their parents and from society (“be successful but be faithful to our traditions”; “be integrated but remember you are an immigrant”), they find it difficult to escape from social processes that assign them a devalued identity of difference and they are obliged to construct new forms of identity. Such issues about identity are common to the decline of modernity’s traditional modes of inheritance and genealogical transmission. However, the huge gap between the socialisation context of immigrant parents and that of their children as well as the impact of social domination are such that the processes of identity formation among Moroccan immigrants are particularly complicated

Measuring an orienteer's performance: a method based on lower rank approximation of asymmetric matrices

The objective of this thesis is to develop a method that measures the performance of competitors in an orienteering course. The measures proposed will allow the comparison of the orienteer’s performance with other competitors running the same course, and with his/her performance in different courses. This thesis presents two main contributions, the first one refers to an orienteer’s performance measure, and the second one relates to the lower rank approximation theory developed for this research. In the orienteering context, we developed a method that calculates a fitness measure and a navigational measure for each orienteer running a course. This differentiation between physical and navigational skills is an original approach to the orienteering performance analysis, and it allows a clear identification of areas that need improvement to achieve better times in an event. Based on the performance measures of orienteers participating in 100 events that took place in the UK between January 2013 and May 2014, we construct a course technical difficulty measure for green, blue and brown courses. This course difficulty allows the identification of easy and hard courses. On the statistical theory context, this thesis presents a robust and asymmetric lower rank approximation algorithm to reduce matrices with asymmetric outliers into two vectors. This algorithm was based on the robust lower rank approximation algorithm proposed by Maronna and Yohai (2008). This thesis presents two original modifications to this algorithm, which produces better estimates when the data has asymmetric outliers. Those modifications are the definition of an asymmetric objective function, and the use of a robust scale parameter that is updated at each iteration. The proposed modification to the scale parameter caused that the estimates do not depend anymore on initial values and the value reached by the loss function is most of the time better than the point reached without the modification. We also show that this methodology can be applied in contexts other than orienteering

The Divine Right of Judges: How Christian Thought Shaped the American Judiciary

This Essay continues a discussion on the authority of courts, executives, and legislators to govern nations where the law diverges from necessity or morality. In a previous Comment, P. Elise McLaren, Answering the Call: A History of the Emergency Power Doctrine in Texas and United States, 53 St. Mary’s L.J. 287 (2022), I asked whether necessity or emergency ever supersedes the law, i.e., whether “emergency powers” exist. In this Essay, I ask whether the government is held accountable to a force other than the people themselves, namely, religious influence. As was done with respect to emergency powers, I ask whether a religious influence is beneficial, detrimental, or neutral, and secondarily whether it is necessary

The Divine Right of Judges: How Christian Thought Shaped the American Judiciary

This Essay continues a discussion on the authority of courts, executives, and legislators to govern nations where the law diverges from necessity or morality. In a previous Comment, P. Elise McLaren, Answering the Call: A History of the Emergency Power Doctrine in Texas and United States, 53 St. Mary’s L.J. 287 (2022), I asked whether necessity or emergency ever supersedes the law, i.e., whether “emergency powers” exist. In this Essay, I ask whether the government is held accountable to a force other than the people themselves, namely, religious influence. As was done with respect to emergency powers, I ask whether a religious influence is beneficial, detrimental, or neutral, and secondarily whether it is necessary

The Impact of Shoreline Stabilization on Sediment Supply and Ecogeomorphology: Assessing Marsh Response to Altered Wave Energies, Lake Borgne, Louisiana

Shoreline protection structures are a common response to lateral erosion in marshes, but limited studies exist on how they influence sediment supply and the resulting ecogeomorphology. This study investigates the impacts of marine mattresses, geotextile cages filled with riprap, in Lake Borgne, LA. A field study was conducted during cold front passages at a site with marine mattresses and a proximal control site without, collecting measurements of water depth, wave energy, lateral erosion, sediment accumulation, vegetation, and sediment characteristics. Wetlands with marine mattresses attenuated waves more than their natural marsh edge counterparts, which have limited conditions favorable for sedimentation. However, the lateral position of the marsh was maintained, while the control site eroded at an average rate of 1.7 meters per year. Water content, organic matter, bulk density, salinity, and pH were similar between the sites, but the marine mattress site was lower in elevation and contained finer sediments