Search results for "convergence [keyword]"
showing 10 items of 30 documents
On implementation of the Gibbs sampler for estimating the accuracy of multiple diagnostic tests
2010
Implementation of the Gibbs sampler for estimating the accuracy of multiple binary diagnostic tests in one population has been investigated. This method, proposed by Joseph, Gyorkos and Coupal, makes use of a Bayesian approach and is used in the absence of a gold standard to estimate the prevalence, the sensitivity and specificity of medical diagnostic tests. The expressions that allow this method to be implemented for an arbitrary number of tests are given. By using the convergence diagnostics procedure of Raftery and Lewis, the relation between the number of iterations of Gibbs sampling and the precision of the estimated quantiles of the posterior distributions is derived. An example conc…
Convergence Rates for Persistence Diagram Estimation in Topological Data Analysis
2014
International audience; Computational topology has recently seen an important development toward data analysis, giving birth to the field of topological data analysis. Topological persistence, or persistent homology, appears as a fundamental tool in this field. In this paper, we study topological persistence in general metric spaces, with a statistical approach. We show that the use of persistent homology can be naturally considered in general statistical frameworks and that persistence diagrams can be used as statistics with interesting convergence properties. Some numerical experiments are performed in various contexts to illustrate our results.
Inductive E.S.O. model evolution: towards a viable inference model of resilience dynamics.
2013
In this paper, we will present the last evolution of the Territorial Intelligence (TI) networking vulnerability model. To introduce it, we'll first describe a well-known late 80's model of socio-economic crack-up, known as "Silent Weapons for Quiet Wars", constituted by three passive components as potential energy, kinetic energy, and energy dissipation. To extend this model to social and ecological sustainability pillars, we propose to present the E(Economic)-S(Social)-O(Organic) IT-collaborative model, based on the three sustainability capitals. Goal of this model is the developement system viability computation, which related "Viability theory" computational framework is able to define s…
Reliable numerical solution of a class of nonlinear elliptic problems generated by the Poisson-Boltzmann equation
2020
We consider a class of nonlinear elliptic problems associated with models in biophysics, which are described by the Poisson-Boltzmann equation (PBE). We prove mathematical correctness of the problem, study a suitable class of approximations, and deduce guaranteed and fully computable bounds of approximation errors. The latter goal is achieved by means of the approach suggested in [S. Repin, A posteriori error estimation for variational problems with uniformly convex functionals. Math. Comp., 69:481-500, 2000] for convex variational problems. Moreover, we establish the error identity, which defines the error measure natural for the considered class of problems and show that it yields computa…
Quels sont les déterminants de la composition des conseils d'administration ? Le cas des entreprises belges, françaises et suisses
2008
International audience; Nous comparons la composition des conseils d'administration (CA) dans trois pays européens: la Belgique, la France, et la Suisse, sur la période 2001-2006. Nos analyses mettent en évidence l'influence de la structure de propriété des entreprises. sur la composition des CA, mais les évolutions constatées résultent également de l'application des codes de gouvernance.
Electromagnetic wave propagation in non-homogeneous waveguides
2015
We investigate an electromagnetic waveguide, having several cylindrical ends. The waveguide is assumed to be empty and to have a perfectly conductive boundary. We study the electromagnetic field, excited in the waveguide in the presence of charges and currents. The field can be described as a solution of the stationary Maxwell system with conductive boundary conditions and “intrinsic” radiation conditions at infinity. We prove the problem to be well-posed. Electromagnetic waves propagation in the waveguide can be described by means of a scattering matrix. We introduce such a matrix for all values of the spectral parameter k in the waveguide continuous spectrum and study its properties. Moreove…
Espiral. Cuadernos del profesorado
2016
Vicente Peydró fue una de las figuras artísticas más destacadas de la Valencia de finales del siglo XIX y principios del XX, en una etapa que se denomina Renaixença. Su trabajo como compositor, periodista, poeta, actor y dibujante le convirtieron en una persona sumamente conocida, querida y respetada por todos los valencianos. En el presente trabajo se realiza una propuesta didáctica desde la metodología de Aprendizaje por Proyectos (PBL) en el alumnado de secundaria y bachillerato. La figura de Peydró es idónea para enseñar a nuestros alumnos de secundaria los valores que deben regir en el arte, ya que este autor demostró poseer unos inquebrantables principios morales. Asimismo, su eclécti…
Relationships between stomatognathic and oculomotor systems in the postural determinism
2009
Objectives To establish if oculomotor apparatus, stomatognathic apparatus and postural system are someway related. Materials and methods Ocular deficit, postural stabilization, head inclination and rotation, shoulder position and dental class were assessed by convergence test, cover test, postural and stomatognathic examination in a sample of 22 patients with ocular disease (convergence deficit, strabismus and heterophoria) aged from 10 to 18 years. Results In patients with convergence's deficit, body axis deviated to left (65%) and head inclination to right (65%), right shoulder was higher (68%) and I dental class was observed (49%); in patients with strabismus, body axis deviated to left …
Broglie and Young, visionaries who shed light in the polar topology that grounds our reality: a hypothesis
2020
Una observación matemática que relaciona los patrones fractales y la operación de convolución en el contexto del procesamiento de imágenes digitales interrumpió una investigación que nos lleva a plantear la hipótesis de que el concepto de onda de materia (o dualidad onda-partícula) se encuentra en la dicotomía entre el par débil y un topología fuerte en el ámbito del marco de atractores singulares continuos en ninguna parte diferenciables y el concepto de fotón-solitón de Vigier. Tal inferencia parece ser más evidente en la interpretación de Broglie-Bohm de la mecánica cuántica en el cruce de características locales x globales. De esto se deduce también que la relación de los fenómenos natu…
Convergence of Measures
2020
One focus of probability theory is distributions that are the result of an interplay of a large number of random impacts. Often a useful approximation can be obtained by taking a limit of such distributions, for example, a limit where the number of impacts goes to infinity. With the Poisson distribution, we have encountered such a limit distribution that occurs as the number of very rare events when the number of possibilities goes to infinity (see Theorem 3.7). In many cases, it is necessary to rescale the original distributions in order to capture the behavior of the essential fluctuations, e.g., in the central limit theorem. While these theorems work with real random variables, we will a…