An excursion approach to maxima of the Brownian Bridge

Functionals of Brownian bridge arise as limiting distributions in nonparametric statistics. In this paper we will give a derivation of distributions of extrema of the Brownian bridge based on excursion theory for Brownian motion. Only the Poisson character of the excursion process will be used. Particular cases of calculations include the distributions of the Kolmogorov-Smirnov statistic, the Kuiper statistic, and the ratio of the maximum positive ordinate to the minumum negative ordinate.Comment: 20 page

The effect of binocular and monocular distractors on saccades in participants with normal binocular vision

We tested the effect of visual distractors presented monocularly and binocularly on saccade latency and accuracy to determine whether differences occur in saccadic planning with binocular or monocular visual input. For five participants with normal binocular single vision (BSV), saccade latency and accuracy were compared with distractors presented to the dominant eye, non-dominant eye or to both eyes. Eye movements of the dominant eye were recorded using a Skalar infra-red recorder. In the presence of normal BSV, the effect of distractors is significantly larger for saccade latency and accuracy with binocular distractor presentation than for monocular presentations, with no difference between distrators presented to the dominant or non-dominant eye. The implications of these results are discussed with regard to saccade programming

Redshift distributions of galaxies in the Dark Energy Survey Science Verification shear catalogue and implications for weak lensing

We present photometric redshift estimates for galaxies used in the weak lensing analysis of the Dark Energy Survey Science Verification (DES SV) data. Four model- or machine learning-based photometric redshift methods—ANNZ2, BPZ calibrated against BCC-Ufig simulations, SKYNET, and TPZ—are analyzed. For training, calibration, and testing of these methods, we construct a catalogue of spectroscopically confirmed galaxies matched against DES SV data. The performance of the methods is evaluated against the matched spectroscopic catalogue, focusing on metrics relevant for weak lensing analyses, with additional validation against COSMOS photo-z’s. From the galaxies in the DES SV shear catalogue, which have mean redshift 0.72 0.01 over the range 0.3 < z < 1.3, we construct three tomographic bins with means of z ¼ f0.45; 0.67; 1.00g. These bins each have systematic uncertainties δz ≲ 0.05 in the mean of the fiducial SKYNET photo-z nðzÞ. We propagate the errors in the redshift distributions through to their impact on cosmological parameters estimated with cosmic shear, and find that they cause shifts in the value of σ8 of approximately 3%. This shift is within the one sigma statistical errors on σ8 for the DES SV shear catalogue. We further study the potential impact of systematic differences on the critical surface density, Σcrit, finding levels of bias safely less than the statistical power of DES SV data. We recommend a final Gaussian prior for the photo-z bias in the mean of nðzÞ of width 0.05 for each of the three tomographic bins, and show that this is a sufficient bias model for the corresponding cosmology analysis

The Dark Energy Survey : more than dark energy – an overview

This overview paper describes the legacy prospect and discovery potential of the Dark Energy Survey (DES) beyond cosmological studies, illustrating it with examples from the DES early data. DES is using a wide-field camera (DECam) on the 4 m Blanco Telescope in Chile to image 5000 sq deg of the sky in five filters (grizY). By its completion, the survey is expected to have generated a catalogue of 300 million galaxies with photometric redshifts and 100 million stars. In addition, a time-domain survey search over 27 sq deg is expected to yield a sample of thousands of Type Ia supernovae and other transients. The main goals of DES are to characterize dark energy and dark matter, and to test alternative models of gravity; these goals will be pursued by studying large-scale structure, cluster counts, weak gravitational lensing and Type Ia supernovae. However, DES also provides a rich data set which allows us to study many other aspects of astrophysics. In this paper, we focus on additional science with DES, emphasizing areas where the survey makes a difference with respect to other current surveys. The paper illustrates, using early data (from ‘Science Verification’, and from the first, second and third seasons of observations), what DES can tell us about the Solar system, the Milky Way, galaxy evolution, quasars and other topics. In addition, we show that if the cosmological model is assumed to be +cold dark matter, then important astrophysics can be deduced from the primary DES probes. Highlights from DES early data include the discovery of 34 trans-Neptunian objects, 17 dwarf satellites of the Milky Way, one published z > 6 quasar (and more confirmed) and two published superluminous supernovae (and more confirmed)

Scalimétrie et caractérisation des modèles de croissance pour une population de truites sédentaires

DEU

The project of a LTSER site Driven by civil society in the Argonne

International audienc

Approches méthodologiques dans l'étude de l'acceptabilité de la vaccination : exemple de trois enquêtes menées en Afrique de l'Ouest

Daniel Lévy-Bruhl, J. Cook, B. Legonou, Y. Jaffré, P. Amévigbe, G. Sanou, N. Guérin: Methodological approaches in studying the acceptability of vaccination: example of three investigations conducted in West Africa. Immunization program directors in three West African countries asked the help of social scientists to better understand non-utilization of immunization services. Semi-structured interviews carried out in homes sought to identify how parental models of childhood illnesses, especially concepts of their causes and prevention, affect immunization levels. These studies are examples of applied social science research providing, in a matter of months, information useful to health personnel for the management of their programs.Résumé : Afin de mieux appréhender les motifs de non-utilisation des services de vaccination, les responsables de programmes de vaccination de trois pays d'Afrique de l'Ouest ont fait appel aux méthodes des sciences sociales. Des entretiens semi-structures menés auprès des familles ont tenté de préciser comment les modèles parentaux des maladies de l'enfance et surtout les concepts sur leurs causes et leur prévention influencent la couverture vaccinale infantile. Ces études représentent des exemples de recherche appliquée en sciences sociales permettant en quelques mois de fournir aux cadres de la santé des informations utiles à la gestion de leurs programmes.Daniel Lévy-Bruhl, et al. : Un enfoque metodológico en el estudio de la aceptabilidad de la vacunación : très encuestas llevadas a cabo en Africa del Oeste. Con el fin de comprender mejor los motivos de la no utilización de los servicios de vacunación, los responsables de los programas de vacunación de très paises de Africa del Oeste recurieron a la metodo- logfa de las ciencias sociales. Entrevistas semiestructuradas fueron llevadas a cabo con las familias. Intentaron precisar de qué manera los modelos parentales de las enfermedades de la infancia y sobretodo los conceptos relacionados con sus causas y su prevención influyen en la cobertura de la vacunación infantil. Dichos estudios representan ejemplos de la investigación aplicada en ciencias sociales que permite a los responsables de la salud adquirir en solo unos meses la información necesaria para la aplicación de sus programas.Lévy-Bruhl Daniel, Cook Jon, Legonou B., Jaffré Yannick, Amévigbe P., Sanou G., Guérin N. Approches méthodologiques dans l'étude de l'acceptabilité de la vaccination : exemple de trois enquêtes menées en Afrique de l'Ouest. In: Sciences sociales et santé. Volume 11, n°2, 1993. Aspects des systèmes de santé dans les pays du Sud, sous la direction de Bernard Hours et Jérôme Dumoulin. pp. 9-25