Radioactivity half-lives considered as data.
A method is introduced to select the significant or non null mean terms among a collection of independent random variables. As an application we consider the problem of recovering the significant coefficients in non ordered model selection. The method is based on a convenient random centering of the partial sums of the ordered observations. Based on L-statistics methods we show consistency of the proposed estimator. An extension to unknown parametric distributions is considered. Simulated examples...
Background: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), a novel strain of MRSA, has recently emerged and rapidly spread in the community. Invasion into the hospital setting with replacement of the hospital-acquired MRSA (HA-MRSA) has also been documented. Co-colonization with both CA-MRSA and HA-MRSA would have important clinical implications given differences in antimicrobial susceptibility profiles and the potential...
The objective of this paper is to introduce some recursive methods that can be used for estimating an value. These methods can be used more generally for the estimation of the -quantile of an unknown distribution provided we have 0-1 observations at our disposal. Standard methods based on the Robbins-Monro procedure are introduced together with different approaches of Wu or Mukerjee. Several examples are also mentioned in order to demonstrate the usefulness of the methods presented.
This paper proposes an asymptotic rejection algorithm on the rejection of nonharmonic periodic disturbances for general nonlinear systems. The disturbances, which are produced by nonlinear exosystems, are nonharmonic and periodic. A new nonlinear internal model is proposed to deal with the disturbances. Further, a state feedback controller is designed to ensure that the system's state variables can asymptotically converge to zero, and the disturbances can be completely rejected. The proposed algorithm...
This paper deals with the reliability of composite measurement consisting of true-false items obeying the Rasch model. A definition of reliability in the Rasch model is proposed and the connection to the classical definition of reliability is shown. As a modification of the classical estimator Cronbach's alpha, a new estimator logistic alpha is proposed. Finally, the properties of the new estimator are studied via simulations in the Rasch model.
En este trabajo se describe una metodología que nos permite representar simultáneamente poblaciones estadísticas y variables aleatorias, así como transformaciones admisibles de las mismas. Para ello se representan las variables aleatorias, o sus transformadas, en el espacio tangente a la variedad de las poblaciones estadísticas, a continuación se proyectan en dicha variedad y, finalmente, se aplica un análisis canónico de poblaciones para su representación en un espacio de dimensión reducida. Los...
Los campos escalares, bidimensionales y dependientes del tiempo, se representan generalmente en Meteorología mediante una sucesión de imágenes o análisis separados con una interdistancia temporal adecuada. Esta técnica alcanza su máximo desarrollo en lo que se conoce como gráfico animado.En el presente artículo se describen brevemente los procesos que, a partir de los datos, culminan con la generación de un análisis, imagen o fotograma, particularizando al caso de episodios de lluvia. Tras un resumen...