Gilles R. Ducharme

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• PhD
• Professor (Emeritus) at Université de Montpellier

We introduce two new tools to assess the validity of statistical distributions. These tools are based on components derived from a new statistical quantity, the $comparison$ $curve$. The first tool is a graphical representation of these components on a $bar$ $plot$ (B plot), which can provide a detailed appraisal of the validity of the statistical...

The Newcomb-Benford probability distribution is becoming very popular in many areas using statistics, notably in fraud detection. In such contexts, it is important to be able to determine if a data set arises from this distribution while controlling the risk of a Type 1 error, i.e. falsely identifying a fraud, and a Type 2 error, i.e. not detecting...

This paper develops a test of goodness-of-fit for elliptical distributions. The test is invariant to affine-linear transformations and has a convenient expression that can be broken into components containing diagnostic information to be used to identify possible departures when the test rejects. The test is developed for the bivariate Laplace, log...

This paper develops a smooth test of goodness-of-fit for elliptical distributions. The test is adaptively omnibus, invariant to affine-linear transformations and has a convenient expression that can be broken into components. These components have diagnostic capabilities and can be used to identify specific departures. This helps in correcting the...

This paper introduces an estimator of the signalto-noise ratio in the framework where a noisy source emits the same signal a number n of times. The estimator has the structure of a U-statistic from which derives many desirable properties: it is unbiased, consistent and, being a Rao-Blackwellisation of existing proposals, is closer to optimal varian...

This paper considers the problem of choosing a good classifier. For each problem there exist an optimal classifier, but none are optimal, regarding the error rate, in all cases. Because there exists a large number of classifiers, a user would rather prefer an all-purpose classifier that is easy to adjust, in the hope that it will do almost as good...

Résumé Dans une série chronologique {Xt,t≥1}, Xj est un record supérieur si Xj>max⁡{X1,…,Xj−1}. Des modèles populaires pour de telles données sont le modèle de Yang–Nevzorov et le modèle à dérive linéaire. Dans cette note, nous présentons la vraisemblance jointe de la suite des records et de leur indicatrice d’occurrence. Cette vraisemblance peut e...

Let {Xt, t = 1} be a time series. A (upper) record is a value Xj such that Xj> max{X1,…,Xj-1}. Some popular models in record theory are the Yang-Nevzorov and the Linear Drift models. The stochastic behavior of records under these models has been much studied and many interesting distribution-free properties have been unearthed. However the estimati...

The wide attention given to the mutual information analysis (MIA) is often connected to its statistical genericity, denoted flexibility in this paper. Indeed, MIA is expected to lead to successful key recoveries with no reliance on a priori knowledge about the implementation (impacted by the error modeling made by the attacker. and with as minimum...

This paper introduces a statistical procedure, to be applied after a goodness-of-fit test has rejected a null model, that provides diagnostic information to help the user decide on a better model. The procedure goes through a list of departures, each being tested by a local smooth test. The list is organized into a hierarchy by seeking answers to t...

Soit X 1 , ..., X n une suite de variables aléatoires. Le record (supérieur) dans cette suite est la valeur M n telle que M n = max (X 1 ,. .. , X n). Un des modèles populaires en théorie de records est le Linear Drift Model (LDM), qui suppose que X n = Y n + cn, où c est le paramètre de dérive. Ce modèle a été étudié sur le plan probabiliste où on...

In this paper, we propose to study the impact of 28nm FDSOI technology on energy study. In fact, due to the effects of the Moore’s law, the process variations in current technologies are increasing and have a major impact on power and performance which results in parametric yield loss. Due to this, process variability and the difficulty of modeling...

This paper first reviews some basic properties of the (noncircular) complex multinormal distribution and presents a few characterizations of it. The distribution of linear combinations of complex normally distributed random vectors is then obtained, as well as the behavior of quadratic forms in complex multinormal random vectors. We look into the p...

Due to the effects of the Moore's law, the process variations in current technologies are increasing and have a major impact on power and performance which results in parametric yield loss. Due to this, process variability and the difficulty of modeling accurately transistor behavior impede the dimensions scaling benefits. The Fully Depleted Silico...

Due to the effects of the Moore's law, the process variations in current technologies are increasing and have a major impact on power and performance which results in parametric yield loss. Due to this, process variability and the difficulty of modeling accurately transistor behavior impede the dimensions scaling benefits. The Fully Depleted Silico...

Mutual Information Analysis (MIA) has a main advantage over Pearson's correlation Analysis (CPA): its ability in de- tecting any kind of leakage within traces. However, it re- mains rarely used and less popular than CPA; probably be- cause of two reasons. The �rst one is related to the appropri- ate choice of hyperparameters involved in MIA, choice...

This paper first reviews some basic properties of the (noncircular) complex multinormal distribution and presents a few characterizations of it. The distribution of linear combinations of complex normally distributed random vectors is then obtained, as well as the behavior of quadratic forms in complex multinormal random vectors. We look into the p...

The use of Dynamic Voltage and Frequency Scaling technique (DVFS) in Systems-on-Chip is becoming more and more common. This technique, re-named RDVFS for the occasion, has recently been proposed as a countermeasure against Side Channel Attacks (SCA) through the randomization of the choices of V and F, at the expense of power consumption. In this pa...

Recently, a generic DPA attack using the mutual information index as the side channel distinguisher has been introduced. Mutual Information Analysis's (MIA) main interest is its claimed genericity. However, it requires the estimation of various probability density functions (PDF), which is a task that involves the complicated problem of selecting t...

FATP1 is involved in lipid transport into cells and in intracellular lipid metabolism. We showed previously that this protein interacts with and inhibits the limiting-step isomerase of the visual cycle RPE65. Here, we aimed to analyze the effect of Fatp1-deficiency in vivo on the visual cycle, structure and function, and on retinal aging. Among the...

Monte Carlo (MC) method is the standard method to characterize statistical moments of cell delays and slopes. However, this method suffers from very high computational cost. In this paper, we propose a technique to quickly and accurately estimate Standard Deviation (SD) of standard cell delays and slopes. The proposed technique is based on the iden...

We introduce an omnibus goodness-of-fit test for statistical models for the conditional distribution of a random variable. In particular, this test is useful for assessing whether a regression model fits a data set on all its assumptions. The test is based on a generalization of the Cramér–von Mises statistic and involves a local polynomial estimat...

Vortices could play an important role in the occurrence of certain biological phenomena, such as the massive proliferation of harmful algae in bodies of water. Many measures exist to detect vortices in fluids, but little is known about the stochastic behavior of these quantities with data that contain statistical noise. Consequently they do not pro...

To characterize statistical moments of cell delays and slopes, the standard method is Monte Carlo (MC) method. However, this method suffers from very high computational cost. In this paper, we propose a technique to quickly and accurately estimate Standard Deviation (SD) of standard cell delays and slopes. The proposed technique is based on the ide...

Corner-based Timing Analysis (CTA) becomes more and more pessimistic as feature size shrinks. This trend has motivated the development of Statistical Static Timing Analysis (SSTA). In this paper, we propose a new path-based SSTA framework that allows the estimation of path delay distributions and delay correlations by propagating iteratively mean a...

Estimation of delay correlations is one of the most challenging problems in SSTA. This is because cell delay depends on a number of factors in a complex manner, which makes complex the estimation of correlations as well. In this paper, we introduce a technique to compute cell-to-cell and path-to-path delay correlations, which allows considering the...

Statistical Static Timing Analysis (SSTA) is becoming necessary, but has not been widely adopted due to various weaknesses. In this paper, we address one of the challenging problems in SSTA: computation of correlations between cell delays. With the help of conditional moments, cell-to-cell and path-to-path delay correlations are computed by propaga...

Statistical Static Timing Analysis (SSTA) is becoming necessary; but has not been widely adopted. One of those arguments against the use is that results of SSTA are difficult to make use of for circuit design. In this paper, by introducing conditional moments, we propose a path-based statistical timing approach, which permits us to consider gate to...

Abstract—Statistical static timing analysis (SSTA) is becoming necessary, but has not been widely adopted. One of those arguments against the use is that results of SSTA are difficult to interpret and to make use of for further topics. In this paper, by introducing conditional moment from probability theory, we propose a path-based statistical timi...

It has been recognized that Classification trees (CART) are unstable; a small perturbation in the input variables or a fresh sample can lead to a very different classification tree. Some approaches exist that try to correct this instability. However, their benefits can, at present, be appreciated only qualitatively. A similarity measure between two...

In a regression model with univariate response, the quantities derived from the least-absolute-deviations method need not be unique. In this note, we show that, contrary to the univariate case, in a regression model with multivariate response, the least-distances method typically yields quantities that exhibit uniqueness properties that are similar...

We propose an estimator of the concentration parameter of the Langevin distribution that is based on the spatial median. We derive its asymptotic distribution, compute its asymptotic efficiency, and show that it possesses some interesting stability properties under contamination.Cet article propose un estimateur du paramètre de concentration d'une...

Statistical static timing analysis (SSTA) is becoming complicated due to introduction of more and more advanced statistical techniques. In this paper, with the help of conditional moments, we propose a simple path-based timing approach, which permits us to consider gate topology and switching process induced correlations. Numerical results are pres...

A retrospective study was performed of 181 horses that underwent an exploratory celiotomy because of acute abdominal disease. Forty-four horses died or were euthanized during surgery. Of the 137 horses that recovered from anesthesia, 72 died of associated diseases or complications, 86 were discharged from the hospital of which 60 survived at least...

The authors studied the time of conception of 280 fetuses and liveborns with anencephaly or spina bifida seen in a French Canadian population during a period of six years. There is an evident seasonal variation in the conception of NTD fetuses. Using a wave statistical model applied to data recorded over a six year period the authors have rejected...

We propose an optimal choice for the bandwidth parameter used in the local polynomial estimation of the conditional distribution function. This choice is approximated by the bandwidth which minimizes the asymptotic weighted mean integrated squared error (MISE). To cite this article: S. Ferrigno, G.R. Ducharme, C. R. Acad. Sci. Paris, Ser. I 346 (20...

Ce document présente, dans le cadre d'une étude en mathématiques appliquées sur des données longitudinales de richesse en sucre de la canne, le passage de l'application à la résolution d'un problème théo-rique original. Nous montrons que la question posée par l'application est souvent en relation avec un domaine théorique large. Un effort de compré...

We propose a global test of goodness-of-fit to assess the validity of an entertained statistical model by testing simultaneously all the assumptions made about it. This test is based on a local polynomial estimator of the conditional distribution function and on the standard paradigm relating the distance between the nonparametric estimator and the...

Bacro Jean-Noël Président du Jury Berlinet Alain Examinateur Ducharme Gilles Directeur de Thèse Harel Michel Rapporteur Saracco Jérôme Examinateur Sarda Pascal Rapporteur

We propose a goodness-of-fit test for growth curves based on an adaptation of the data-driven smooth test paradigm. It is simple to apply and can assess the fit of a model to a set of growth experiences. A simulation study shows that for small samples, the test holds its level. Moreover, its power is found to be generally greater than existing test...

In this paper, we propose a goodness-of-fit test of normality for the innovations of an ARMA(p, q) model with known mean or trend. The test is based on the data driven smooth test approach and is simple to perform. An extensive simulation study is conducted to study the behaviour of the test for moderate sample sizes. It is found that our approach...

We propose a goodness-of-fit test for monotonous nonlinear regression models. The test is based on an adaptation, to the regression context, of the smooth test paradigm of Neyman (1937) for testing the distribution of a sample. We complete his approach with a data-driven criterion for the test's parameters. To cite this article: B. Fontez, G.R. Duc...

The notion of efficient test for a Euclidean parameter in a semiparametric model was introduced by Stein [Proc. Third Berkeley Symp. Math. Statist. Probab. 1 (1956) 187-195]. Such tests are locally most powerful for a wide class of infinite-dimensional nuisance parameters. The first formal application of this notion to a suitably parametrized two-s...

In this paper, we develop an approximation for the most powerful invariant test of one location-scale family against another one. The approach is based on the Laplace method for integrals and yields a very accurate approximation of the density of a maximal invariant. Moreover, it can be applied to a much wider set of pairs of densities than previou...

In this paper, we develop an approximation for the most powerful invariant test of one location-scale family against another one. The approach is based on the Laplace method for integrals and yields a very accurate approximation of the density of a maximal invariant. Moreover, it can be applied to a much wider set of pairs of densities than previou...

The local linear estimator of the conditional cumulative distribution function is shown to be the ratio of two U-statistics. Using results from the theory of U-statistics, we show the almost sure convergence of this estimator both locally and globally. This is used to establish the almost sure convergence of conditional quantiles computed from the...

In this paper, tests of goodness-of-fit for the inverse Gaussian distribution are developed. The distribution involves a shape parameter and, because of this, some test approaches lead to inconsistent strategies. A consistent test is proposed and its properties investigated. A table of critical points is provided and both the level and the power of...

To determine, in North American children, reference values for respiratory resistance measurements by the forced oscillation (Rfo) technique and to examine whether sitting height, as index of truncal length, is a better determinant of resistance, less influenced by race and gender, than standing height. A prospective cross-sectional study of health...

In regression analysis, a best subset of regressors is usually selected by minimizing Mallows's C statistic or some other equivalent criterion, such as the Akaike lambda information criterion or cross-validation. It is known that the resulting procedure suffers from a lack of consistency that can lead to a model with too many variables. For this re...

In this paper we develop, for directional and axial data, smooth tests of goodness-of-fit for rotationally symmetric distributions against general families of embedding alternatives constructed from complete orthonormal bases of functions. These families generalize a proposal of Beran (1979) based on spherical harmonics. Combined with Rao's score t...

Premature terminations or dropouts occur often in repeated measurement experiments. A number of methods have been proposed to analyze such data but most of them assume that the censoring mechanism is, within each group, unaffected by the mechanism generating the response variables. In this paper, we propose a model for the censoring mechanism that...

In this paper, we study the problem of estimating non-parametrically a quantile regression curve as it applies to computing reference values. We propose an automatic procedure that uses a symmetrized nearest-neighbor kernel estimator of conditional distributions. We also discuss ways of measuring the dispersion of quantile regression estimator. One...

We show that the test statistic given by J. C. W. Rayner and D. J. Best [ibid. 73, 437-446 (1986; Zbl 0604.62040)] for J. Neyman’s [Skand. Aktuarie Tidskr. 20, 149-199 (1937; Zbl 0018.03403)] smooth test of goodness of fit for location-scale families does not, in general, have the alleged chi-squared distribution. As a result, gross error may resul...

Directional data analysis usually assumes that the observations are recorded according to a coordinate system whose origin coincides with the center of their support. However, it may happen that the observer does not sit at this center and record the directions from another point. The object of this paper is to investigate the statistical behavior...

To establish the rate of spontaneous closure of atrial septal defects diagnosed before age 3 months, 101 infants (mean age 26 days) with an interatrial shunt confirmed by Doppler echocardiography were followed up for an average of 265 +/- 190 days. Even if interatrial shunts in the newborn are frequently encountered, little is known about their nat...

Objectives. To establish the rate of spontaneous closure of atrial septal defects diagnosed before age 3 months, 101 infants (mean age 26 days) with an interatrial shunt confirmed by Doppler echocardiography were followed up for an average of 265 ± 190 days,Background. Even if interatrial shunts in the newborn are frequently encountered, little is...

A range-gated Doppler ultrasound system combined with a real-time imaging system was used to determine arterial blood velocity values from the fetal and placental ends of the umbilical cord in 269 normal pregnancies between 17 and 40 weeks, menstrual age. The systolic-diastolic ratio (S/D), pulsatility index (PI), and resistance index (RI) were hig...

A four-parameter generalization of the Gompertz curve is proposed which passes through the origin with respect to total age and is often more suitable for somatic growth than the three-parameter Gompertz curve. Applied to published cross-sectional data on 44 male white rats, the new curve differs from another four-parameter curve proposed earlier b...

Sotalol is a beta-blocker with class III antiarrhythmic properties that has recently been used in children for the treatment of supraventricular and ventricular arrhythmias. However, little is known about its electrophysiologic effects on the immature heart. Using intracardiac electrocardiographic recordings and stimulation techniques, 15 canine ne...

Sampling experiments are done on the maximum likelihood estimator, k = tan (f), of the slope of the bivariate normal major axis, which is often used on log-transformed data to estimate allometry exponents. The slope tan (f) becomes highly variable in small samples from populations with low correslations. Moreover, the corresponding angle, f = arc t...

Two hundred twenty-four consecutive patients operated on for tetralogy of Fallot were followed from 1 to 28 years (mean 11). Mean age at surgery was 5.3 years (range 1 to 14). Postoperative right ventricular systolic pressure was 60 mm Hg in 19 of 213 patients (9%). Fourteen patients (6%) had ventricular premature complexes on surface electrocardio...

In order to determine which variables are useful and accurate in estimating prognosis in horses with abdominal pain, data were analyzed from 231 horses presented at a veterinary teaching hospital. Using multiple stepwise discriminant analysis in a recursive partition model, we obtained a decision protocol that identified survivors and nonsurvivors....

In order to determine which variables are useful in identifying horses with abdominal pain requiring surgery, data were analysed from 219 horses presented at one veterinary teaching hospital. Using multiple stepwise discriminant analysis with a recursive partitioning algorithm, we obtained a decision tree that identifies surgical and non-surgical p...

A measure of multivariate correlation between two sets of vectors is considered when the underlying joint distribution is a member of the class of elliptical distributions. Its asymptotic distribution is derived under different situations and these results are used to test hypotheses on vector correlation when the underlying joint distribution is n...

In cardiac allografts acute rejection produces deleterious effects on blood flow adjustments. In order to differentiate the role of rejection over that of denervation cardiac denervated and cardiac transplanted dogs were compared. A canine model of orthotopic cardiac transplantation was utilized. Electronic devices were implanted for chronic hemody...

Unlabelled: In order to assess possible changes in myocardial relaxation occurring during the neonatal period, M-mode echocardiograms were recorded serially in 9 normal term infants and in another group of 10 one-month-old infants. The tracings were studied with an M-mode calculator. Although individual variations were greater in the data collecte...

The purpose of this note is to show that if a probability measure on a Euclidean space is not concentrated on a line, then its spatial median is unique.

We introduce the normalized spatial median as an estimator of location for rotationally symmetric distributions on the hypersphere. We investigate some of its asymptotic properties and use them to obtain confidence regions for the modal direction of a distribution on the hypersphere. These results are then applied to the von Mises-Fisher distributi...

The asymptotic distribution of the circular median is derived for symmetric distributions on the circle. Its asymptotic relative efficiency with respect to the mean direction and to an stimator proposed by G. S. Watson [Statistics on spheres (1983; Zbl 0646.62045)] is then examined. Special attention is given to the cases where the underlying distr...

In search of reliable criteria that could help differentiate insignificant atrial septal defects (ASDs) from those with a large shunt, M-mode echocardiograms of three groups of patients were studied retrospectively: group I = 10 normal children (mean age 5.7 years); group II = 10 patients (mean age 7 years) with small ASD in whom the decision was t...

To determine the effects of maternal hyperglycemia on fetal hemodynamic and cardiac function, a study was carried out on nine chronically catheterized fetal sheep. In six fetuses, glucose was infused intravenously with an initial dose of 5 mg/kg per min. Data were compared with controls. This dose was gradually increased to 16 mg/kg per min by the...

Fifty-one patients with uncomplicated transposition of the great arteries (TGA) and normal pulmonary pressure who were 10 to 20 years old and 69 normal subjects matched for age were studied by M mode echocardiography. Left ventricular internal dimensions and posterior wall thickness showed positive correlation with the body surface area in the TGA...

Following the study on psychomaintenance of asthma by Kinsman, Dirks, and Jones (1977), we adapted the Battery for Asthma Illness Behavior (BAIB) to children. Thirty-four children aged 9.3 to 15.4 years were tested with this modified BAIB. They were scored simultaneously on a semistructured psychological interview. Three groups emerged out of these...

Until recently intra-abdominal sepsis following surgery for perforated appendicitis has remained a frequent occurrence. In 1975 Fowler reported an incidence of one intra-abdominal abscess in 36 perforated appendicitis treated with a protocol consisting of saline irrigation at surgery, followed by intraperitoneal administration of cephaloridine q. 6...

To determine whether acute alcohol ingestion during pregnancy could affect fetal myocardial function, studies were carried in six chronically catheterized fetal sheep during maternal alcohol infusion. Absolute ethyl alcohol (0.8 ml/kg) was administered to the mother over 10 minutes via the jugular vein. These infusions were repeated every 30 minute...

Isolated partial anomalous pulmonary venous drainage (PAPVD), in contrast to atrial septal defect (ASD), does not cancel out the effects of respiration on blood flow in the right ventricle. The aim of this study was to see whether this difference could contribute to the diagnosis of PAPVD without ASD on M mode echocardiography. The diastolic dimens...

In this note, BUNKE and RIEMER'S [3] empirical investigation of the bootstrap for testing linear hypotheses is reviewed. It is shown that the formal bootstrap procedure investigated by them, which performed rather poorly, can be modified to give a better approximation of the test statistic's exact sampling distribution, This is then substantiated b...

In this article, the problem of testing for the collapsibility of a contingency table is studied. The notion of collapsibility is first discussed and three aspects of this property are distinguished. Tests for these three forms are presented, with attention focussed on 2 × 2 × K tables. Finally, it is shown that in a collapsible table, the marginal...

Given a sample from a distribution F supported on a p-dimensional sphere, several confidence cones for the ‘mean directional vector’ are proposed. Some methods have been available, but they depend on parametric assumptions. In this paper, nonparametric confidence cones based on the bootstrap are considered, and consistency of these methods is obtai...

Records of two veterinary teaching hospitals from January 1, 1976 to June 1, 1982 were searched for diagnoses of stifle lameness. Forty-two records were found and information was recorded regarding signalment, history and clinical presentation. The following abnormalities were associated with stifle lameness: subchondral bone cyst (18 cases), joint...

Echocardiographic assessment of cardiac function was made on 24 children with chronic renal failure of varying etiology and severity. In 20 patients without evidence of cardiac failure, parameters of left ventricular performance as represented by PEP/LVET and mean velocity of circumferential fiber shortening were within normal limits in the majorit...

This preliminary study evaluated phenoxymethyl penicillin (Penicillin V) as an alternative to parenteral administration of penicillin in horses. Penicillin V was administered orally to five horses at two different doses and plasma levels of the drug were determined at timed intervals. The results were evaluated by regression analysis. Following the...

A computerized study of past infectious events and neurological parameters revealed the existence of a history of repeated respiratory-tract infections (RRI) beginning in childhood, in 52% of 251 multiple sclerosis (MS) patients studied. The 251 MS patients were divided into two groups: those without a past history of RRI were designated as "MS typ...