Stephan Morgenthaler

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All rights reserved.Context. Strongly lensed quasars are fundamental sources for cosmology. The Gaia space mission covers the entire sky with the unprecedented resolution of 0.18âÃ Â€ ³ in the optical, making it an ideal instrument to search for gravitatio ...

A fundamental statistical problem is to indicate which of two hypotheses is better supported by the data. Statistics designed for this purpose are called weight of evidence. In this paper we study the problem of robust weights of evidence, optimal in their performance while robust in the infinitesimal sense of the influence function.

Context. The first Gaia Data Release contains the Tycho-Gaia Astrometric Solution (TGAS). This is a subset of about 2 million stars for which, besides the position and photometry, the proper motion and parallax are calculated using Hipparcos and Tycho-2 po ...

This paper discusses the estimation of regression parameters after summarizing the data by a covariance matrix of the concatenated vector of explanatory variables and response variable. A robust estimate of the covariance matrix leads to a robust regression estimator. An M-estimator at the covariance estimation step is studied in the paper, and the resulting regression estimator is compared to a few previously proposed robust regression estimators.

Robust procedures increase the reliability of the results of a data analysis. We studied such a robust procedure for binary regression models based on the criterion of least absolute deviation. The resulting estimating equation consists in a simple modific ...

The role of Bifidobacterium species and microbial metabolites such as short-chain fatty acids (SCFAs) and human milk oligosaccharides in controlling intestinal inflammation and the pathogenesis of obesity and type 1 diabetes (T1D) has been largely studied ...

We extend a basic result of Huber's on least favorable distributions to the setting of conditional inference, using an approach based on the notion of log-Gâteaux differentiation and perturbed models. Whereas Huber considered intervals of fixed width for l ...

Physiological Brain connectivity and spontaneous interaction between regions of interest of the brain can be represented by a matrix (full or sparse) or equivalently by a complex network called connectome. This representation of brain connectivity is adopt ...

The Neyman-Scott rectangular pulses model is a clustered point process in time. This article presents a new method of parameters estimation for this model applied to rainfall simulation. It is based on a modified method of moments using two temporal scales of aggregation. A simple algebraic computation leads to reduce the number of parameters estimated by minimisation. Indeed two parameters are obtained by minimisation while the three others can be directly computed. The optimisation method used is based on

Context. The third Gaia Data Release (DR3) provided photometric time series of more than 2 million long-period variable (LPV) candidates. Anticipating the publication of full radial-velocity data planned with Data Release 4, this Focused Product Release (F ...

Familial adenomatous polyposis coli (FAP) has been shown to be associated with germline mutations of the adenomatous polyposis gene (APC) on chromosome 5. Extra-colonic manifestations also occur in FAP and include desmoid tumors, epidermoid cysts and osteomas. The combination of FAP with extracolonic symptoms is commonly referred to as Gardner's syndrome. It remains difficult, however, to predict which patients may have a propensity to develop extracolonic manifestations. The rapid acetylation phenotype is

We argue that robust statistics has multiple goals, which are not always aligned. Robust thinking grew out of data analysis and the realisation that empirical evidence is at times supported merely by one or a few observations. The paper examines the outgro ...

Cycling temperature capillary electrophoresis has been optimised for mutation detection in 76% of the mitochondrial genome. The method was tested on a mixed sample and compared to mutation detection by next generation sequencing. Out of 152 fragments 90 we ...

Diffuse interstellar bands (DIBs) are absorption features seen in optical and infrared spectra of stars and extragalactic objects that are probably caused by large and complex molecules in the galactic interstellar medium (ISM). Here we investigate the Gal ...

We consider the problem of testing positively dependent multiple hypotheses assuming that a prior information about the dependence structure is available. We propose two-step multiple comparisons procedures that exploit the prior information of the dependence structure, without relying on strong assumptions. In the first step, we group the tests into subsets where tests are supposed to be positively dependent and in each of which we compute the standardized mean of the test scores. Given the subset mean sco

We apply the univariate sliced inverse regression to survival data. Our approach is different from the other papers on this subject. The right-censored observations are taken into account during the slicing of the survival times by assigning each of them w ...

The article studies estimation of Delta = p(1) - p(2), the difference of two proportions p(1) and p(2), based on two independent Binomial experiments of size n(1) and n(2). The usual estimator, the difference between the two sample proportions, is variance ...

The combination of evidence from independent studies has a curious history. The origins reach back at least to the beginning of the 20th century. Since the mid-1970s, meta-analysis has become popular in several fields, among them medical statistics and the ...

In a sailboat race, the navigator's attempts to plot the fastest possible course are hindered by shifty winds. We present mathematical models appropriate for this situation, which use statistical analysis of wind fluctuations and are amenable to stochastic ...

Context. We report the exploitation of a sample of Solar System observations based on data from the third Gaia Data Release (Gaia DR3) of nearly 157 000 asteroids. It extends the epoch astrometric solution over the time coverage planned for the Gaia DR4, w ...

Stephan Morgenthaler

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Gaia Focused Product Release: A catalogue of sources around quasars to search for strongly lensed quasars

Optimal weights of evidence with bounded influence

Gaia Data Release 1 Open cluster astrometry: performance, limitations, and future prospects

Robust regression through robust covariances

Robust binary regression

Innovative Biomarkers for Obesity and Type 1 Diabetes Based on Bifidobacterium and Metabolomic Profiling

Conditionally least-informative distributions: The case of the location parameter

Statistical methods for comparing brain connectomes at different scales

Unbiased parameter estimation of the Neyman-Scott model for rainfall simulation with related confidence interval

Gaia Focused Product Release: Radial velocity time series of long-period variables

Association of extracolonic manifestations of familial adenomatous polyposis with acetylation phenotype in a large FAP kindred

A survey of robust statistics

Cycling temperature capillary electrophoresis: A quantitative, fast and inexpensive method to detect mutations in mixed populations of human mitochondrial DNA

Gaia Focused Product Release: Spatial distribution of two diffuse interstellar bands

Two step multiple comparisons procedures for positively dependent data with application to detecting differences in human brain network topologies

Sliced inverse regression for survival data

Variance Stabilizing the Difference of Two Binomial Proportions

Combining Statistical Evidence

Stochastic optimization of sailing trajectories in an upwind regatta

Gaia Focused Product Release: Asteroid orbital solution: Properties and assessment