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Analysis of survey data investigating the malarial endemicity of a mixed tribal population of Bihar, India.

T. K. Basu, S. Ganguly, B. K. Sarkar, Raghunath Arnab (1998)

Qüestiió

A section of the mixed tribal population of the Singhbhum district, Bihar, India, is declared malaria epidemic zone. The tribal population of several generations is known to be suffering from malaria. A survey based on cross-sectional data analysis, was conducted on the mixed tribal population for one month. The purpose of this study was to investigate the health status using collected blood samples. The main focus is on the comparative roles of the defense mechanism and vitality factor of the human...

Analysis on the individual efficiency prediction in the composed error frontier model. A Monte Carlo study.

Rafaela Dios Palomares, Antonio Ramos Millán, José Angel Roldán-Casas (2002)

Qüestiió

This study seeks to analyse some important questions related to the Stochastic Frontier Model, such as the method proposed by Jondrow et al (1982) to separate the error term into its two components, and the measure of efficiency given by Timmer (1971). To this purpose, a Monte Carlo experiment has been carried out using the Half-Normal and Normal-Exponential specifications throughout the rank of the γ parameter. The estimation errors have been eliminated, so that the intrinsic variability of the...

ANOVA using commutative Jordan algebras, an application

Paulo Canas Rodrigues, João Tiago Mexia (2006)

Discussiones Mathematicae Probability and Statistics

Binary operations on commutative Jordan algebras are used to carry out the ANOVA of a two layer model. The treatments in the first layer nests those in the second layer, that being a sub-model for each treatment in the first layer. We present an application with data retried from agricultural experiments.

Aplicació de l'anàlisi multivariant a un estudi sobre les llengües europees.

Francesc Oliva, Catalina Bolancé, L. Díaz (1993)

Qüestiió

Utilizando una información compleja y cualitativa (la escritura de los dos primeros nombres) se presenta un método que permite cuantificar adecuadamente las diferencias entre catorce lenguas europeas construyendo una matriz de distancias. Para realizar el estudio comparativo se emplean dos técnicas de análisis multivariante: el análisis de proximidades ("multidimensional scaling") y el análisis jerárquico de conglomerados ("hierarchical cluster analysis").

Aplicación de modelos de Wiener-Levy a datos biomédicos.

Charles B. Bell, F. Ramírez, E. P. Smith (1985)

Trabajos de Estadística e Investigación Operativa

Para varios conjuntos de datos biomédicos, se quiere hacer inferencia sobre la función media de la población. La mayoría de los métodos clásicos para este tipo de inferencia han sido derivados bajo el supuesto de que los datos constituyen muestras aleatorias de una población normal. Pero en realidad, en el campo médico, pocas veces se tienen muestras aleatorias. El problema práctico principal es hallar un modelo de dependencia entre los datos que aproxime la situación real y que sea manejable desde...

Apollo 13 Risk Assessment Revisited

Bukovics, István (2007)

Serdica Journal of Computing

Fault tree methodology is the most widespread risk assessment tool by which one is able to predict - in principle - the outcome of an event whenever it is reduced to simpler ones by the logic operations conjunction and disjunction according to the basics of Boolean algebra. The object of this work is to present an algorithm by which, using the corresponding computer code, one is able to predict - in practice - the outcome of an event whenever its fault tree is given in the usual form.

Application of biregressional designs to electrodialytic removal of heavy metals from contaminated matrices

Alexandra B. Ribeiro, Eduardo P. Mateus (2010)

Discussiones Mathematicae Probability and Statistics

Given a base design with quantitative factors and a primary linear regression to each of the treatments, we may adjust secondary regressions of linear combinations of the adjusted coefficients on the primary regressions on the factor levels, thus obtaining a biregressional model. A biregressional design was established for a set of treatments, defined from quantitative factors and a linear regression in the same variables. Afterwards the action of the regression coefficients...

Application of HLM to data with multilevel structure

Vítor Valente, Teresa A. Oliveira (2011)

Discussiones Mathematicae Probability and Statistics

Many data sets analyzed in human and social sciences have a multilevel or hierarchical structure. By hierarchy we mean that units of a certain level (also referred micro units) are grouped into, or nested within, higher level (or macro) units. In these cases, the units within a cluster tend to be more different than units from other clusters, i.e., they are correlated. Thus, unlike in the classical setting where there exists a single source of variation between observational units, the heterogeneity...

Application of MCMC to change point detection

Jaromír Antoch, David Legát (2008)

Applications of Mathematics

A nonstandard approach to change point estimation is presented in this paper. Three models with random coefficients and Bayesian approach are used for modelling the year average temperatures measured in Prague Klementinum. The posterior distribution of the change point and other parameters are estimated from the random samples generated by the combination of the Metropolis-Hastings algorithm and the Gibbs sampler.

Application of the random field theory in PET imaging - injection dose optimization

Jiří Dvořák, Jiří Boldyš, Magdaléna Skopalová, Otakar Bělohlávek (2013)

Kybernetika

This work presents new application of the random field theory in medical imaging. Results from both integral geometry and random field theory can be used to detect locations with significantly increased radiotracer uptake in images from positron emission tomography (PET). The assumptions needed to use these results are verified on a set of real and simulated phantom images. The proposed method of detecting activation (locations with increased radiotracer concentration) is used to quantify the quality...

Application of the Rasch model in categorical pedigree analysis using MCEM: I binary data

G. Qian, R. M. Huggins, D. Z. Loesch (2004)

Discussiones Mathematicae Probability and Statistics

An extension of the Rasch model with correlated latent variables is proposed to model correlated binary data within families. The latent variables have the classical correlation structure of Fisher (1918) and the model parameters thus have genetic interpretations. The proposed model is fitted to data using a hybrid of the Metropolis-Hastings algorithm and the MCEM modification of the EM-algorithm and is illustrated using genotype-phenotype data on a psychological subtest in families where some members...

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