Search results for "Sondage"
showing 6 items of 6 documents
Penalization and data reduction of auxiliary variables in survey sampling
2012
Survey sampling techniques are quite useful in a way to estimate population parameterssuch as the population total when the large dimensional auxiliary data setis available. This thesis deals with the estimation of population total in presenceof ill-conditioned large data set.In the first chapter, we give some basic definitions that will be used in thelater chapters. The Horvitz-Thompson estimator is defined as an estimator whichdoes not use auxiliary variables. Along with, calibration technique is defined toincorporate the auxiliary variables for sake of improvement in the estimation ofpopulation totals for a fixed sample size.The second chapter is a part of a review article about ridge re…
Robust estimation of mean electricity consumption curves by sampling for small areas in presence of missing values
2017
In this thesis, we address the problem of robust estimation of mean or total electricity consumption curves by sampling in a finite population for the entire population and for small areas. We are also interested in estimating mean curves by sampling in presence of partially missing trajectories.Indeed, many studies carried out in the French electricity company EDF, for marketing or power grid management purposes, are based on the analysis of mean or total electricity consumption curves at a fine time scale, for different groups of clients sharing some common characteristics.Because of privacy issues and financial costs, it is not possible to measure the electricity consumption curve of eac…
Estimate the mean electricity consumption curve by survey and take auxiliary information into account
2012
In this thesis, we are interested in estimating the mean electricity consumption curve. Since the study variable is functional and storage capacities are limited or transmission cost are high survey sampling techniques are interesting alternatives to signal compression techniques. We extend, in this functional framework, estimation methods that take into account available auxiliary information and that can improve the accuracy of the Horvitz-Thompson estimator of the mean trajectory. The first approach uses the auxiliary information at the estimation stage, the mean curve is estimated using model-assisted estimators with functional linear regression models. The second method involves the au…
Contribution à l'estimation non paramétrique des quantiles géométriques et à l'analyse des données fonctionnelles
2008
In this dissertation we study the nonparametric geometric quantile estimation, conditional geometric quantiles estimation and functional data analysis. First, we are interested to the definition of geometric quantiles. Different simulations show that Transformation-Retransformation technique should be used to estimate geometric quantiles when the distribution is not spheric. A real study shows that, data are better modelized by geometric quantiles than by marginal one's, especially when variables that make up the random vector are correlated. Then we estimate geometric quantiles when data are obtained by survey sampling techniques. First, we propose an unbaised estimator, then using lineari…
L'opinion publique : de la science politique au droit ?
2016
Publication partielle des actes du colloque "L'opinion publique : de la science politique au droit ?", organisé par le Centre de recherche en droit et science politique (CREDESPO) de l'Université de Bourgogne, les 16 et 17 octobre 2014; National audience; L'opinion publique est partout. Il n'y a plus guère d'analyse politique, institutionnelle ou économique qui puisse faire aujourd'hui l'économie du recours à des sondages ou autres modes d'expression qui convoquent et mettent en scène l'opinion. La page de la démocratie représentative semble tournée. Et celle de la démocratie directe, largement impraticable, ou politiquement dangereuse, n'est pas à l'ordre du jour. Il ne semble donc exister…
Géostatistique, radio sondages et modèles numériques à aire limitée : données et méthodes croisées pour l'étude d'un événement froid en France.
2011
6 pages; International audience; Durant la nuit du 19-20 décembre 2009, un bref événement froid a provoqué des dégâts notables au sein duvignoble de Côte d’Or (France). Nous cherchons à documenter les mécanismes à l'origine de cet événement au moyend'observations (températures et radio sondages) et de simulations issues de deux modèles numériques à aire limitée(ALADIN et WRF). Une interpolation de type régression-kriging réalisée sur les températures stationnelles met en évidenceun gradient thermique est-ouest doublé d'une poche froide sur la plaine de Saône. Relevant de deux échelles distinctes, cettegéographie est associée à un flux synoptique de nord et à des inversions thermiques expliq…