Search results for "Statistical"
showing 10 items of 4960 documents
Dealing with spatial data pooled over time in statistical models
2012
Recent developments in spatial econometrics have been devoted to spatio-temporal data and how spatial panel data structure should be modeled. Little effort has been devoted to the way one must deal with spatial data pooled over time. This paper presents the characteristics of spatial data pooled over time and proposes a simple way to take into account unidirectional temporal effect as well as multidirectional spatial effect in the estimation process. An empirical example, using data on 25,357 single family homes sold in Lucas County, OH (USA), between 1993 and 1998 (available in the MatLab library), is used to illustrate the potential of the approach proposed.
Infant mortality gap in the Baltic region - Latvia, Estonia, and Lithuania - in relation to macroeconomic factors in 1996-2010.
2013
Background and Objective. A constant gap has appeared in infant mortality among the 3 Baltic States - Latvia, Estonia, and Lithuania – since the restoration of independence in 1991. The aim of the study was to compare infant mortality rates in all the 3 Baltic countries and examine some of the macro- and socioeconomic factors associated with infant mortality. Material and Methods. The data were obtained from international databases, such as World Health Organization and EUROSTAT, and the national statistical databases of the Baltic States. The time series data sets (1996–2010) were used in the regression and correlation analysis. Results. In all the 3 Baltic States, a strong and significant…
Validação de um questionário de satisfação sobre a formação prática de estudantes de enfermagem
2019
Objetivo: validar un instrumento para valorar la formación práctica y la satisfacción con las asignaturas de Practicum de los estudiantes de Enfermería. Método: estudio observacional, descriptivo, transversal (curso 2014-2015). Validación de un cuestionario autoadministrado y anónimo (17 ítems) de Satisfacción sobre el Practicum en Estudiantes de Enfermería, elaborado por consenso de ocho expertos en formación práctica (en tres sesiones de grupo nominal). Se realizó análisis factorial y confirmatorio, estimándose la consistencia interna para determinar su validez. Se calculó la satisfacción de los estudiantes en cada asignatura y en su totalidad. Resultados: 174 respuestas. Alta correlación…
An application of the arithmetic euler function to the construction of nonclassical states of a quantum harmonic oscillator
2001
Abstract All quantum superpositions of two equal intensity coherent states exhibiting infinitely many zeros in their Fock distributions are explicitly constructed and studied. Our approach is based on results from number theory and, in particular, on the properties of arithmetic Euler function. The nonclassical nature of these states is briefly pointed out. Some interesting properties are brought to light.
Stochastic response determination of nonlinear oscillators with fractional derivatives elements via the Wiener path integral
2014
A novel approximate analytical technique for determining the non-stationary response probability density function (PDF) of randomly excited linear and nonlinear oscillators endowed with fractional derivatives elements is developed. Specifically, the concept of the Wiener path integral in conjunction with a variational formulation is utilized to derive an approximate closed form solution for the system response non-stationary PDF. Notably, the determination of the non-stationary response PDF is accomplished without the need to advance the solution in short time steps as it is required by the existing alternative numerical path integral solution schemes which rely on a discrete version of the…
Prospective de la relation formation-emploi dans un territoire : Richesse des outils, cohérence de l'analyse et incohérence dans l'action
2005
05111; Cette contribution porte sur la prospective en matière de relation formation-emploi tant au niveau régional qu'européen : où en sommes-nous de la capacité de mobilisation de l'information économique et sociale ? Jusqu'à quel point le partage de l'information entre acteurs régionaux est-il possible ? Quel est le rôle des informations dans l'aide à la décision ? Quel est le rapport de la connaissance à l'action ? La réflexion s'appuie sur une comparaison des démarches prospectives mises en oeuvre dans le secteur de l'hôtellerie-restauration dans certaines régions de trois pays européens : la France, la Tchéquie et la Slovénie. Elle souligne la richesse de l'outil statistique existant p…
Deep-Time Phylogenetic Clustering of Extinctions in an Evolutionarily Dynamic Clade (Early Jurassic Ammonites)
2012
7 pages; International audience; Conservation biologists and palaeontologists are increasingly investigating the phylogenetic distribution of extinctions and its evolutionary consequences. However, the dearth of palaeontological studies on that subject and the lack of methodological consensus hamper our understanding of that major evolutionary phenomenon. Here we address this issue by (i) reviewing the approaches used to quantify the phylogenetic selectivity of extinctions and extinction risks; (ii) investigating with a high-resolution dataset whether extinctions and survivals were phylogenetically clustered among early Pliensbachian (Early Jurassic) ammonites; (iii) exploring the phylogene…
PACo: a novel procrustes application to cophylogenetic analysis.
2013
We present Procrustean Approach to Cophylogeny (PACo), a novel statistical tool to test for congruence between phylogenetic trees, or between phylogenetic distance matrices of associated taxa. Unlike previous tests, PACo evaluates the dependence of one phylogeny upon the other. This makes it especially appropriate to test the classical coevolutionary model that assumes that parasites that spend part of their life in or on their hosts track the phylogeny of their hosts. The new method does not require fully resolved phylogenies and allows for multiple host-parasite associations. PACo produces a Procrustes superimposition plot enabling a graphical assessment of the fit of the parasite phyloge…
Sheep habit during hand milking, and relations between the incorrect hand milking procedure and mammary health
2023
This study aimed: (1) to evaluate the relation between the incorrect hand milking and mammary health; (2) to test the hypothesis of the ewe habit in the workstation, of their choice, during the milking. Teat moisturization with foam milk collected from the milk tank represents a high-risk factor because potentially contain mastitis-causing bacteria previously released from affected ewes. Moreover, it was found that sheep are routinary animals by habit during hand milking.
INTERFACE TENSION AND CORRELATION LENGTH OF 2D POTTS MODELS: NUMERICAL VERSUS EXACT RESULTS
1994
I briefly review new analytical formulas for the correlation length and interface tension of two-dimensional q-state Potts models and compare them with numerical results from recent Monte Carlo simulation studies.