Conditional quantile estimation through optimal quantization

In this paper, we use quantization to construct a nonparametric estimator of conditional quantiles of a scalar response $Y$ given a d-dimensional vector of covariates $X$. First we focus on the population level and show how optimal quantization of $X$, which consists in discretizing $X$ by projecting it on an appropriate grid of $N$ points, allows to approximate conditional quantiles of $Y$ given $X$. We show that this is approximation is arbitrarily good as $N$ goes to infinity and provide a rate of convergence for the approximation error. Then we turn to the sample case and define an estimator of conditional quantiles based on quantization ideas. We prove that this estimator is consistent for its fixed-$N$ population counterpart. The results are illustrated on a numerical example. Dominance of our estimators over local constant/linear ones and nearest neighbor ones is demonstrated through extensive simulations in the companion paper Charlier et al.(2014b)

Towards a Complete Static Analyser for Java: an Abstract Interpretation Framework and its Implementation

AbstractWe present an abstract interpretation framework for a subset of Java (without concurrency). The framework uses a structural abstract domain whose concretization function is parameterized on a relation between abstract and concrete locations. When structurally incomptatible objects may be referred to by the same variable at a given program point, structural information is discarded and replaced by an approximated information about the objects (our presentation concentrates on type information). Plain structural information allows precise intra-procedural analysis but is quickly lost when returning from a method call. To overcome this limitation, relational structural information is introduced, which enables a precise inter-procedural analysis without resorting to inlining.The paper contains an overview of the work. We describe parts of the standard and abstract semantics; then, we briefly explain the fixpoint algorithms used by our implementation; lastly, we provide experimental results for small programs

NEDOVRŠENA SMRTONOSNA TREPANACIJA UTVRĐENA NA KREMIRANIM OSTACIMA (RIM, ITALIJA, II. ST.)

Background: An original case of incomplete (and reasonably fatal) human trepanation is described in this short paper. The diagnosis was made on the cremated remains of a young adult individual who died in Rome, Italy during the 2nd century AD. Clinical Presentation: The trepanation was incomplete, as death occurred quickly due to vascular lesions, according to the anatomic analysis of the bone piece. Comparable trepanation from Roman times are described and related to this case. Conclusion: Even if archaeological, this case highlights the possibility of such a diagnosis on post-fire fragmented bones. Very suggestive lesions of section are of great interest for the history of such a practice during classical Antiquity. Lastly, from a medical and forensic point of view, such a diagnosis may be of interest during any identification process and research for a cause of death during anthropological analyses.Uvod: Ovaj kratki rad opisuje izvorni slučaj nedovršene, fatalne trepanacije. Dijagnoza trepanacije postavljena je temeljem pregleda kremiranih ostataka mlade odrasle osobe umrle u II. stoljeću u Rimu. Klinička slika: Anatomskom analizom kostiju utvrđena je nedovršena trepanacija, vjerojatno zbog smrti koja je nastupila netom nakon početka zahvata kao posljedica oštećenja krvožilja. Uz to, prikazani nalaz uspoređuje se sa sličnim slučajevima trepanacije iz rimskog razdoblja. Zaključak: Iako temeljen na arheološkim ostacima, ovaj slučaj ističe mogućnost dijagnosticiranja trepanacije iz kremiranih i fragmetniranih koštanih ostataka. Sugestivna oštećenja utvrđena na koštanom materijalu od značajnog su interesa za povijest trepanacije u klasičnoj antici. Također, ovakav slučaj može biti od interesa medicinskoj struci tijekom identifikacijskih procesa i antropološkog utvrđivanja uzroka smrti iz koštanih ulomaka

Wiederverwendungsstudie I - Kommunale Aufgaben und Refinanzierung: Reichweite und Refinanzierung von Aktivitäten der öffentlich-rechtlichen Entsorgungsträger bei der Vorbereitung zur Wiederverwendung

Im Zuge einer Prüfung der öffentlich-rechtlichen Entsorgungsträger (örE) sollen deren Rechte und Pflichten mit Maßnahmen zur Förderung der Wiederverwendung und Abfallvermeidung, insbesondere durch Information und Beratung der Abfallbesitzer untersucht werden, was Möglichkeiten der Refinanzierung über Gebühren einschließt. Viele Gegenstände, die von ihrem Besitzer einer Abfallsammlung zugeführt werden, sind noch „brauchbar“ und eignen sich für eine unmittelbare weitere Verwendung, könnten zumindest aber mit geringem Aufwand dafür hergerichtet werden. Es werden rechtliche Ansätze ausgelotet, um das Potenzial für eine Wiederverwendung von Erzeugnissen und Bestandteilen von Erzeugnissen zu erhöhen

Transport geography at the turn of the century

The period covered by this bibliographical review (1995-2000) is characterized by an important development of the theoretical researches in transport geography. This new trend is illustrated by a great diversity of materials, which can be divided into three sub-groups: network analysis, modelling techniques and spatial analysis of road transport externalities. But a significant part of papers with a strong descriptive component indicates that empirical studies still constitute a concern of the Belgian geographers, especially in connection with new research areas as the developing world and the geography of cruise shipping.La période couverte par la présente revue bibliographique (1995-2000) est caractérisée par un important développement des recherches théoriques dans le domaine de la géographie des transports. Cette nouvelle tendance est illustrée par une grande diversité de contributions qui peuvent être regroupées en trois sous-catégories: l’analyse des réseaux, les techniques de modélisation et l’analyse spatiale des externalités liées au transport routier. Une part substantielle d’articles présente une composante descriptive importante, ce qui montre que les études à caractère empirique constituent toujours une préoccupation des géographes belges, particulièrement dans les nouveaux domaines de recherche que sont les pays en voie de développement et la géographie des croisières

Conditional Quantile Estimation based on Optimal Quantization: from Theory to Practice

International audienceSmall-sample properties of a nonparametric estimator of conditional quantiles based on optimal quantization, that was recently introduced (J. Statist. Plann. Inference, 156, 14–30, 2015), are investigated. More precisely, (i) the practical implementation of this estimator is discussed (by proposing in particular a method to properly select the corresponding smoothing parameter, namely the number of quantizers) and (ii) its finite- sample performances are compared to those of classical competitors. Monte Carlo studies reveal that the quantization-based estimator competes well in all cases and sometimes dominates its competitors, particularly when the regression function is quite complex. A real data set is also treated. While the main focus is on the case of a univariate covariate, simulations are also conducted in the bivariate case

A glimpse into the early origins of medieval anatomy through the oldest conserved human dissection (Western Europe, 13^th c. A.D.)

INTRODUCTION: Medieval autopsy practice is very poorly known in Western Europe, due to a lack of both descriptive medico-surgical texts and conserved dissected human remains. This period is currently considered the dark ages according to a common belief of systematic opposition of Christian religious authorities to the opening of human cadavers. MATERIAL AND METHODS: The identification in a private collection of an autopsied human individual dated from the 13(th) century A.D. is an opportunity for better knowledge of such practice in this chrono-cultural context, i.e. the early origins of occidental dissections. A complete forensic anthropological procedure was carried out, completed by radiological and elemental analyses. RESULTS: The complete procedure of this body opening and internal organs exploration is explained, and compared with historical data about forensic and anatomical autopsies from this period. During the analysis, a red substance filling all arterial cavities, made of mercury sulfide (cinnabar) mixed with vegetal oil (oleic and palmitic acids) was identified; it was presumably used to highlight vascularization by coloring in red such vessels, and help in the preservation of the body. CONCLUSIONS: Of particular interest for the description of early medical and anatomical knowledge, this “human preparation” is the oldest known yet, and is particularly important for the fields of history of medicine, surgery and anatomical practice

Contribution méthodologique à l’analyse des mouvements résidentiels intercommunaux wallons par la construction de bassins résidentiels (1994-2014)

Résumé Cet article présente l’analyse des mouvements résidentiels intercommunaux en Wallonie sur une période de 20 ans, à partir de données exhaustives. Un exercice de synthèse de ces déménagements est proposé avec l’adaptation d’une méthodologie hiérarchique développée par l’INSEE (Institut de statistique français) pour construire des regroupements d’entités spatiales sur base de données de flux migratoires dans la région Sud de la Belgique, la Wallonie. À partir de données reprenant l’ensemble des déménagements (migrations résidentielles) enregistrés entre communes belges (Local Administrative Units (LAU) 2 selon Eurostat) de 1994 à 2014, la méthodologie permet de rassembler les entités en bassins sur base de l’importance des échanges migratoires que les entités entretiennent entre elles. Plusieurs choix méthodologi­ques ont été posés pour proposer un découpage de la Wallonie en 11 «bassins résidentiels». Un bassin résidentiel correspond au territoire théorique dans lequel les individus (et par extension les ménages) à la recherche d’une nouvelle localisation résidentielle ont tendance à migrer pour répondre à leurs aspirations en termes de logement, en tenant compte de leurs réseaux sociaux et/ou professionnels et des contraintes de coûts du logement et des déplacements. Cette approche permet à la fois de synthétiser la matrice origine-destination entre toutes les entités d’un territoire, mais également de mieux comprendre la structuration de celui-ci. Abstract This article is about residential migrations between municipalities (Eurostat Local Administrative Units (LAU) 2) in Wallonia, the southern region of Belgium. Based on a hierarchical methodology developed by INSEE (French National Institute of Statistics), residential migrations are synthetized so as to build clusters of municipalities that can be grouped together on the basis of their migration flows in the southern region of Belgium, Wallonia. Using data on all migration flows between municipalities in the period from 1994 to 2014, the methodology allows grouping municipalities based on the migratory exchange rates between them. Several choices have been made that lead to a new spatial division of Wallonia in 11 residential catchment areas. Such an area can be defined as a territory on which a person looking for a new residential location is ready to move as such a move would not interfere with his/her social and/or professional networks and would also respect cost constraints related to housing and commuting. This approach allows synthetising migration flows between all municipalities but also a better understanding of the spatial structure of Wallonia

Plasma level monitoring of the major metabolites of diacetylmorphine (heroin) by the "chasing the dragon" route in severe heroin addicts

peer reviewedThe objective of the present study was to verify if severe physical health problems frequently encountered in heroin addicts and the concomitant use of alcohol and legal or illegal drugs other than heroin influenced the pharmacokinetics of the major metabolites of heroin. We conducted a 90 minutes follow-up of the plasma concentrations of the pharmaceutical heroin, named diacetylmorphine (DAM), in patients recruited in a DAM assisted treatment centre. TADAM (Traitement Assisté par DiAcétylMorphine) aimed to compare the efficacy of heroin-assisted treatment (HAT) compared with methadone maintenance treatment (MMT) for heroin users considered as treatment resistant patients and who have severe physical and mental health problems. Eleven patients were recruited. Blood samples were collected at baseline and 15, 45 and 90 minutes after DAM administration. All patients received DAM by the "chasing the dragon" route. Plasma samples were analyzed by a previously described ultra-high pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC/MS-MS) method. A principal component analysis (PCA) was performed and 8 metabolite concentrations ratios were calculated to evaluate the influence of various factors (DAM dose, patient pathologies, concomitant use of medications, methadone, street heroin, alcohol and cocaine) on heroin metabolite pharmacokinetics. It seemed to be not affected by the DAM dose, patient pathologies and the concomitant use of medications, methadone, street heroin and alcohol. Cocaine use was the only parameter which showed differences in heroin pharmacokinetics

Compositional boundary layers trigger liquid unmixing in a basaltic crystal mush

Abstract: The separation of immiscible liquids has significant implications for magma evolution and the formation of magmatic ore deposits. We combine high-resolution imaging and electron probe microanalysis with the first use of atom probe tomography on tholeiitic basaltic glass from Hawaii, the Snake River Plain, and Iceland, to investigate the onset of unmixing of basaltic liquids into Fe-rich and Si-rich conjugates. We examine the relationships between unmixing and crystal growth, and the evolution of a nanoemulsion in a crystal mush. We identify the previously unrecognised role played by compositional boundary layers in promoting unmixing around growing crystals at melt-crystal interfaces. Our findings have important implications for the formation of immiscible liquid in a crystal mush, the interpretations of compositional zoning in crystals, and the role of liquid immiscibility in controlling magma physical properties