Search results for "bayesiana"
showing 10 items of 20 documents
Bayesian approach to urinary ESBL-producing Escherichia coli
2014
This is a retrospective study about the prevalence of ESBL-producing Escherichia coli (EEC) in urinary specimens from patients from the Comunitat Valenciana from January 2007 to December 2008. Data were retrieved from RedMIVA, and Bayesian generalized linear mixed models were considered to study the prevalence of EEC with regard to demographical and microbiological factors. The total number of infections considered was 164,502, the amount of urinary isolates was 70,827 belonging to 49,304 different patients, and 5,161 (7.3%) of the urinary isolates were EEC. Three out of four E. coli were isolated in women (76.8%), men showed higher rates of EEC (9.7% in men vs. 6.5% in women). EEC patients…
Bayesian hierarchical models for analysing the spatial distribution of bioclimatic indices
2017
A methodological approach for modelling the spatial distribution of bioclimatic indices is proposed in this paper. The value of the bioclimatic index is modelled with a hierarchical Bayesian model that incorporates both structured and unstructured random effects. Selection of prior distributions is also discussed in order to better incorporate any possible prior knowledge about the parameters that could refer to the particular characteristics of bioclimatic indices. MCMC methods and distributed programming are used to obtain an approximation of the posterior distribution of the parameters and also the posterior predictive distribution of the indices. One main outcome of the proposal is the …
Radiocarbono y estadística Bayesiana: aportaciones a la cronología de la Edad del Bronce en el extremo oriental del sudeste de la península Ibérica
2014
La investigación arqueológica desarrollada en las últimas décadas ha permitido evaluar que en los valles de los ríos Segura y Vinalopó se dirimió el contacto entre dos sociedades de la Edad del Bronce de la península Ibérica: el grupo Argárico y el grupo del Prebético Meridional Valenciano. Las excavaciones realizadas en tres yacimientos de este ámbito - Terlinques, Cabezo Pardo y Cabezo Redondo- y las dotaciones de radiocarbono obtenidas permiten por primera vez evaluar la diacronía del proceso histórico que envolvió el desarrollo de ambos grupos arqueológicos a lo largo del II milenio cal BC, así como determinar diversos momentos socialmente significativos en su devenir histórico. Para el…
Modelling spatially sampled proportion processes
2018
Many ecological processes are measured as proportions and are spatially sampled. In all these cases the standard procedure has long been the transformation of proportional data with the arcsine square root or logit transformation, without considering the spatial correlation in any way. This paper presents a robust regression model to analyse this kind of data using a beta regression and including a spatially correlated term within the Bayesian framework. As a practical example, we apply the proposed approach to a spatio-temporally sampled fishery discard dataset.
Editorial: Methodological issues in psychology and social sciences research
2023
In recent decades, the classical methods of studying the psychometric properties of tests have advanced to evolve into new innovative statistical methods, which allows obtaining a new view of the data. In this sense, progress has been made in the use of item response theory and in the use of structural equation models. Likewise, classical statistical inference methods have advanced in hypothesis testing and Bayesian statistics is rapidly making its way both in experimental studies and in psychometric studies. The aim of this issue has been to contribute to the dissemination of new research methodologies in quantitative and qualitative analysis in Psychology, as well as to evaluate the effec…
Differential analysis of indicators of achievement in objective tests
2003
Often objective tests to evaluate student qualifications are used. However, the selection between different evaluation criteria is in the hands of teachers or evaluators preferences. This investigation offers, briefly, a revision of some strategies utilized for objective evaluation. We also present other alternative strategies to the most classical ones. Afterwards, the strategies of evaluation have been analized with data from 114 subjects, who were evaluated with a test. The results suggest there are two kinds of strategies, one where only students' performance are evaluated, and other, where the test and the students are evaluated at the same time. We also show the fail of concordance be…
Prediction and Surveillance Sampling Assessment in Plant Nurseries and Fields
2022
In this paper, we propose a structured additive regression (STAR) model for modeling the occurrence of a disease in fields or nurseries. The methodological approach involves a Gaussian field (GF) affected by a spatial process represented by an approximation to a Gaussian Markov random field (GMRF). This modeling allows the building of maps with prediction probabilities regarding the presence of a disease in plants using Bayesian kriging. The advantage of this modeling is its computational benefit when compared with known spatial hierarchical models and with the Bayesian inference based on Markov chain Monte Carlo (MCMC) methods. Inference through the use of the integrated nested Laplace app…
Benefits of a dance group intervention on institutionalized elder people: A Bayesian network approach
2018
[EN] The present study aims to explore the effects of an adapted classical dance intervention on the psychological and functional status of institutionalized elder people using a Bayesian network. All participants were assessed at baseline and after the 9 weeks period of the intervention. Measures included balance and gait, psychological well-being, depression, and emotional distress. According to the Bayesian network obtained, the dance intervention increased the likelihood of presenting better psychological well-being, balance, and gait. Besides, it also decreased the probabilities of presenting emotional distress and depression. These findings demonstrate that dancing has functional and …
Social Support and Resilience as Predictors of Prosocial Behaviors before and during COVID-19
2022
The objective of this research was to analyze the relationship between social support and resilience with prosocial behavior before and during the confinement caused by COVID-19. Materials and Methods: The participants were divided into a confined group (228 women and 84 men) and an unconfined group (153 women and 105 men), all of whom were university students. Instruments were applied to measure the variables proposed. Results: Social support predicted 24.4% of the variance in prosocial behavior among women and 12% among men in the confined group; no evidence of this relationship was found in the unconfined groups. Resilience predicted 7% of the variance in prosocial behavior among confine…
Cronología bayesiana aplicada a las intervenciones de Lluís Pericot en Cueva de la Cocina (1941 y 1945)
2017
Este capítulo tiene como objetivo la comprensión de la estratigrafía en Cueva de la Cocina, y más en concreto de las intervenciones realizadas por Pericot en el año 1941 y 1945. Para ello se hará uso del conjunto de dataciones radiocarbónicas disponibles para dichas intervenciones sobre las que se elaborarán diferentes modelos cronológicos a partir de la estadística bayesiana. Finalmente sobre los resultados de la modelización cronológica se discierne en torno a la ocupación mesolítica de la cueva a lo largo del Mesolítico reciente (entidad arqueológica conocida como Mesolítico geométrico), haciendo hincapié en las diferentes fases culturales (Geométrico A y B) y sus rangos cronológicos. Th…