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According to the Atlas of Human Development in Brazil, the income dimension of Municipal Human Development Index (MHDI-I) is an indicator that shows the population's ability in a municipality to ensure a minimum standard of living to provide their basic needs, such as water, food and shelter. In public policy, one of the research objectives is to identify social and economic variables that are associated with this index. Due to the income inequality, evaluate these associations in quantiles, instead of the mean, could be more interest. Thus, in this paper, we develop a Bayesian variable selection in quantile regression models with hierarchical random effects. In particular, we assume a likelihood function based on the Generalized Asymmetric Laplace distribution, and a spike-and-slab prior is used to perform variable selection. The Generalized Asymmetric Laplace distribution is a more general alternative than the Asymmetric Laplace one, which is a common approach used in quantile regression under the Bayesian paradigm. The performance of the proposed method is evaluated via a comprehensive simulation study, and it is applied to the MHDI-I from municipalities located in the state of Rio de Janeiro.

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Dietary habits are determinants in the development of a range of conditions and age-related diseases. We explored the associations of sociodemographic, health-related indicators, and health behavioral factors on dietary guideline compliance in elderly Chileans. We used a cross-sectional design using the publicly available database from the last Chilean National Health Survey (2016−17). The sample of 1831 older adults (≥60 y) from a national representative sample. The dependent variable was compliance with Food Guidelines (FG) (daily consumption of water, dairy, and fruits and vegetables; and weekly consumption of legumes and fish). The independent variables included sociodemographic, health-related, and behavioral factors. Over half (51.8%) of the sample was female and 85.7% belonged to the 60−79 age group. Satisfactory compliance to FG was observed in 3.9% of the sample. In the adjusted analysis, for those between 60 and 79 y, marital status was the only significant variable associated with FG noncompliance (PR: 1.34; 95%CI: 1.04−1.71). For those over 80 y, income of >2 minimum wages (PR: 0.10; 95%CI: 0.02−0.61), living alone (PR: 1.72; 95%CI: 1.20−2.47), and self-reported cardiovascular disease (PR: 0.63; 95%CI: 0.43−0.93) were associated with FG noncompliance. We observed low FG compliance among elderly Chilean adults, especially in the oldest group. Factors associated with the FG compliance was different between age groups.

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We explore how ideas and practices common in Bayesian modeling can be applied to help assess the quality of 3D protein structural models. The basic premise of our approach is that the evaluation of a Bayesian statistical model's fit may reveal aspects of the quality of a structure when the fitted data is related to protein structural properties. Therefore, we fit a Bayesian hierarchical linear regression model to experimental and theoretical 13 Cα chemical shifts. Then, we propose two complementary approaches for the evaluation of such fitting: (a) in terms of the expected differences between experimental and posterior predicted values; (b) in terms of the leave-one-out cross-validation point-wise predictive accuracy. Finally, we present visualizations that can help interpret these evaluations. The analyses presented in this article are aimed to aid in detecting problematic residues in protein structures. The code developed for this work is available on: https://github.com/BIOS-IMASL/Hierarchical-Bayes-NMR-Validation.

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OBJECTIVE: To assess the presence, pattern and magnitude of socioeconomic inequalities on dengue, chikungunya and Zika in Latin America, accounting for their spatiotemporal distribution. METHODS: Using longitudinal surveillance data (reported arboviruses) from Fortaleza, Brazil and Medellin, Colombia (2007-2017), we fit Bayesian hierarchical models with structured random effects to estimate: (i) spatiotemporally adjusted incidence rates; (ii) Relative Concentration Index and Absolute Concentration Index of inequality; (iii) temporal trends in RCIs; and (iv) socioeconomic-specific estimates of disease distribution. The spatial analysis was conducted at the neighbourhood level (urban settings). The socioeconomic measures were the median monthly household income (MMHI) for Brazil and the Socio-Economic Strata index (SES) in Colombia. RESULTS: There were 281 426 notified arboviral cases in Fortaleza and 40 887 in Medellin. We observed greater concentration of dengue among residents of low socioeconomic neighbourhoods in both cities: Relative Concentration Index = -0.12 (95% CI = -0.13, -0.10) in Fortaleza and Relative Concentration Index = -0.04 (95% CI = -0.05, -0.03) in Medellin. The magnitude of inequalities varied over time across sites and was larger during outbreaks. We identified a non-monotonic association between disease rates and socioeconomic measures, especially for chikungunya, that changed over time. The Relative Concentration Index and Absolute Concentration Index showed few if any inequalities for Zika. The socioeconomic-specific model showed increased disease rates at MMHI below US$400 in Brazil and at SES-index below level four, in Colombia. CONCLUSIONS: We provide robust quantitative estimates of socioeconomic inequalities in arboviruses for two Latin American cities. Our findings could inform policymaking by identifying spatial hotspots for arboviruses and targeting strategies to decrease disparities at the local level.

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Os arranjos familiares têm se transformado a partir de diversos processos dinâmicos, como a redução da fecundidade, a emancipação da mulher e sua consequente inserção no mercado de trabalho, o aumento do número de divórcios e a ampliação da expectativa de vida. Essas transformações levaram a uma diminuição do tamanho das famílias e diversificação de sua composição. Diante do surgimento de novas estruturas familiares decorrentes da dinâmica social, este estudo analisa a relação dos arranjos familiares com o desempenho escolar dos alunos do 5º e 9º anos de escolas públicas no Brasil em 2015, a partir dos dados da Prova Brasil. A nota de matemática foi utilizada como medida de desempenho e os efeitos da família foram avaliados a partir da modelagem hierárquica dos dados. Os resultados demonstram pouco efeito dos arranjos familiares sobre a proficiência média em matemática, evidenciando que outros elementos e mediadores relacionados aos resultados escolares, tais como status socioeconômico, trajetória do aluno, hábitos escolares individuais e ambiente da escola, apresentam maior relação com o desempenho escolar do que a composição do arranjo por si só.

Family arrangments have experienced several changes due to dynamic processes, such as reduction of fertility, emancipation of women and their consequent insertion in the labor market, increase in the number of divorces and life expectancy. These changes led to a reduction in the size of families and a diversification of their composition. Given the emergence of new family structures and the changes resulting from social dynamics, this study aimed to analyze the relationship between family arrangements and school performance of 5th and 9th grade students in public schools in Brazil in 2015, with data from Prova Brasil. Math scores were used as a measure of performance and the effects of the family were evaluated using hierarchical modeling of the data. The results showed a small effect of family arrangements on average mathematics proficiency but revealed other elements and mediators related to school results, such as socioeconomic status, student trajectory, individual school habits and the school environment, had a stronger connection with school performance than the composition of the arrangement itself.

Los arreglos familiares se han visto transformados por diversos procesos dinámicos como la reducción de la fecundidad, la emancipación de la mujer y su consecuente inserción en el mercado laboral, el aumento del número de divorcios y de la esperanza de vida. Estos cambios llevaron a una disminución del tamaño de las familias y a una diversificación de su composición. Frente, entonces, al surgimiento de nuevas estructuras familiares y a los cambios resultantes de la dinámica social, este estudio tuvo como objetivo analizar la relación de los arreglos familiares con el desempeño escolar de los estudiantes de quinto y noveno grado de las escuelas públicas de Brasil en 2015, a partir de los datos de Prova Brasil. La puntuación de Matemáticas se utilizó como medida de rendimiento y los efectos de la familia se evaluaron mediante un modelo jerárquico de los datos. Los resultados mostraron poco efecto de los arreglos familiares sobre la competencia promedio en Matemáticas y evidenciaron que otros elementos y mediadores relacionados con los resultados escolares, como el nivel socioeconómico, la trayectoria del estudiante, los hábitos escolares individuales y el entorno escolar, presentaban una mayor relación con el rendimiento escolar que la composición del arreglo en sí.

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ABSTRACT Introduction: Use of antibiotic and bacterial resistance is the result of a complex interaction not completely understood. Objectives: To evaluate the impact of entire antimicrobial use (community plus hospitals) on the incidence of bloodstream infections in intensive care units adjusted by socioeconomic factors, quality of healthcare, and access to the healthcare system. Design: Ecologic study using a hierarchical spatial model. Setting: Data obtained from 309 hospitals located in the state of São Paulo, Brazil from 2008 to 2011. Participants: Intensive care units located at participant hospitals. Outcome: Hospital acquired bloodstream infection caused by MDRO in ICU patients was our primary outcome and data were retrieved from São Paulo Health State Department. Socioeconomic and healthcare indexes data were obtained from IBGE (Brazilian Foundation in charge of national decennial census) and SEADE (São Paulo Planning and Development Department). Information on antimicrobial sales were obtained from IMS Brazil. We divided antibiotics into four different groups (1-4). Results: We observed a direct association between the use of group 1 of antibiotics and the incidences of bloodstream infections caused by MRSA (1.12; 1.04-1.20), and CR-Acinetobacter sp. (1.19; 1.10-1.29). Groups 2 and 4 were directly associated to VRE (1.72; 1.13-2.39 and 2.22; 1.62-2.98, respectively). Group 2 was inversely associated to MRSA (0.87; 0.78-0.96) and CR-Acinetobacter sp. (0.79; 0.62-0.97). Group 3 was inversely associated to Pseudomonas aeruginosa (0.69; 0.45-0.98), MRSA (0.85; 0.72-0.97) and VRE (0.48; 0.21-0.84). No association was observed for third generation cephalosporin-resistant Klebsiella pneumoniae and Escherichia coli. Conclusions: The association between entire antibiotic use and resistance in ICU was poor and not consistent for all combinations of antimicrobial groups and pathogens even after adjusted by socioeconomic indexes. Selective pressure exerted at the community level seemed not to affect the incidences of MDRO infection observed in intensive care setting.

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INTRODUCTION: Use of antibiotic and bacterial resistance is the result of a complex interaction not completely understood. OBJECTIVES: To evaluate the impact of entire antimicrobial use (community plus hospitals) on the incidence of bloodstream infections in intensive care units adjusted by socioeconomic factors, quality of healthcare, and access to the healthcare system. DESIGN: Ecologic study using a hierarchical spatial model. SETTING: Data obtained from 309 hospitals located in the state of São Paulo, Brazil from 2008 to 2011. PARTICIPANTS: Intensive care units located at participant hospitals. OUTCOME: Hospital acquired bloodstream infection caused by MDRO in ICU patients was our primary outcome and data were retrieved from São Paulo Health State Department. Socioeconomic and healthcare indexes data were obtained from IBGE (Brazilian Foundation in charge of national decennial census) and SEADE (São Paulo Planning and Development Department). Information on antimicrobial sales were obtained from IMS Brazil. We divided antibiotics into four different groups (1-4). RESULTS: We observed a direct association between the use of group 1 of antibiotics and the incidences of bloodstream infections caused by MRSA (1.12; 1.04-1.20), and CR-Acinetobacter sp. (1.19; 1.10-1.29). Groups 2 and 4 were directly associated to VRE (1.72; 1.13-2.39 and 2.22; 1.62-2.98, respectively). Group 2 was inversely associated to MRSA (0.87; 0.78-0.96) and CR-Acinetobacter sp. (0.79; 0.62-0.97). Group 3 was inversely associated to Pseudomonas aeruginosa (0.69; 0.45-0.98), MRSA (0.85; 0.72-0.97) and VRE (0.48; 0.21-0.84). No association was observed for third generation cephalosporin-resistant Klebsiella pneumoniae and Escherichia coli. CONCLUSIONS: The association between entire antibiotic use and resistance in ICU was poor and not consistent for all combinations of antimicrobial groups and pathogens even after adjusted by socioeconomic indexes. Selective pressure exerted at the community level seemed not to affect the incidences of MDRO infection observed in intensive care setting.

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Helicobacter pylori (H. pylori) is present in the stomach of half of the world's population. The force of infection describes the rate at which susceptibles acquire infection. In this article, we estimated the age-specific force of infection of H. pylori in Mexico. Data came from a national H. pylori seroepidemiology survey collected in Mexico in 1987-88. We modelled the number of individuals with H. pylori at a given age as a binomial random variable. We assumed that the cumulative risk of infection by a given age follows a modified exponential catalytic model, allowing some fraction of the population to remain uninfected. The cumulative risk of infection was modelled for each state in Mexico and were shrunk towards the overall national cumulative risk curve using Bayesian hierarchical models. The proportion of the population that can be infected (i.e. susceptible population) is 85.9% (95% credible interval (CR) 84.3%-87.5%). The constant rate of infection per year of age among the susceptible population is 0.092 (95% CR 0.084-0.100). The estimated force of infection was highest at birth 0.079 (95% CR 0.071-0.087) decreasing to zero as age increases. This Bayesian hierarchical model allows stable estimation of state-specific force of infection by pooling information between the states, resulting in more realistic estimates.

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Household contact studies, a mainstay of tuberculosis transmission research, often assume that tuberculosis-infected household contacts of an index case were infected within the household. However, strain genotyping has provided evidence against this assumption. Understanding the household versus community infection dynamic is essential for designing interventions. The misattribution of infection sources can also bias household transmission predictor estimates. We present a household-community transmission model that estimates the probability of community infection, that is, the probability that a household contact of an index case was actually infected from a source outside the home and simultaneously estimates transmission predictors. We show through simulation that our method accurately predicts the probability of community infection in several scenarios and that not accounting for community-acquired infection in household contact studies can bias risk factor estimates. Applying the model to data from Vitória, Brazil, produced household risk factor estimates similar to two other standard methods for age and sex. However, our model gave different estimates for sleeping proximity to index case and disease severity score. These results show that estimating both the probability of community infection and household transmission predictors is feasible and that standard tuberculosis transmission models likely underestimate the risk for two important transmission predictors. Copyright © 2017 John Wiley & Sons, Ltd.

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Ecological barriers are important determinants of the evolution and distributions marine organisms, and a challenge for evolutionary ecologists seeking to understand population structure in the sea. Dasyatis marianae is an endemic Brazilian species that indicates certain restrictions on its distribution probably due to marine barriers. In this study, Bayesian hierarchical spatial models, jointly with environmental and occurrence species data, are used to identify, which elements could generate these barriers on Dasyatis marianae distribution. Results show that salinity and temperature are the most important drivers that play an essential role to limit the distribution of this species. Indeed, low salinity values restrict Dasyatis marianae distribution in the north of the Brazilian coast, while in the south are colder temperatures. These results highlight the need to better define the distribution of marine species, especially for the ones affected by ecological barriers that are more sensitive to environmental changes.

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Resumo A relevância de um Censo Demográfico para o sistema de estatísticas públicas de uma nação é indiscutível do ponto de vista de sua abrangência temática e territorial. Em contrapartida, sua complexidade e dimensão levam a desafios na garantia da qualidade de seus resultados. O presente artigo tem por objetivo apresentar os possíveis fatores associados a erros não amostrais detectados na coleta das informações, mediante a análise de paradados e dos microdados do Censo Demográfico brasileiro de 2010. Os dados utilizados provêm das informações sobre a operação de coleta e administração da pesquisa oriundas, respectivamente, do sistema de gerenciamento de recursos humanos do pessoal de coleta e do sistema de supervisão da operação de coleta, ou seja, os paradados. Também se utilizam os microdados do universo do Censo Demográfico. Neste estudo foram analisadas as divergências observadas entre as informações coletadas pelos recenseadores e aquelas obtidas por supervisores nas reentrevistas realizadas em procedimentos de supervisão do trabalho de campo. Para análise de divergências detectadas entre os dados coletados por recenseadores e supervisores, foram empregados modelos hierárquicos generalizados. Os resultados mostram que existem diferenciais nas divergências associados à estrutura de coleta dos dados e às características dos recenseadores, supervisores e informantes, além de revelarem diferenças regionais. Fica evidente, sobretudo, uma forte influência das características do informante nas chances de ocorrência das divergências, em detrimento das características dos supervisores e recenseadores. Os resultados da modelagem estatística sugerem que as entrevistas realizadas com informantes do sexo masculino, analfabetos ou com baixa escolaridade, mais velhos e que vivem em domicílios com indicadores que refletem condições de vida menos satisfatórias apresentam aumento nas chances em favor da ocorrência de divergências entre respostas coletadas por recenseador e supervisor.

Abstract The relevance of a population census for a national statistical system is undeniable for its thematic and territorial coverage. Nonetheless, the complexity and size of a census operation lead to challenges for ensuring timeliness and quality of the results. This paper presents potential factors associated with non sampling errors detected in the data collection stage based on the analysis of Brazilian 2010 Population Census microdata and paradata. Data obtained from the field work monitoring system, called paradata, is used to provide information about divergences observed between data collected by enumerators and supervisors, also it is used the census microdata. The latter carried out follow-up interviews in households selected by the supervision/monitoring plan. Human resources databases containing socio-demographic information of enumerators and supervisors is also brought to enhance the analysis. The statistical modeling utilized is generalized hierarchical models, in which the response variable is defined as the occurrence of a discrepancy (or divergence) between the information collected by enumerators and their supervisors. The results indicate that the different hierarchical levels investigated are relevant to decompose data variability and hence have to be considered in the analysis. However, respondents’ characteristics have markedly more influence on the chances of a divergence than those of enumerators’ and supervisors’. In addition, there is evidence that respondents who are male, illiterate (or with low educational level), older and living in households with indicators reflecting poor life conditions present higher odds in favor of the occurrence of divergences on data collected by enumerator and supervisor.

Resumen La relevancia de un censo para el sistema de estadísticas públicas de una nación es indiscutible desde el punto de vista de su cobertura temática y territorial. Por otra parte, su complejidad y dimensión conducen a desafíos para garantizar la calidad de sus resultados. Este artículo tiene como objetivo presentar los posibles factores asociados a errores no muestrales detectados durante el relevamiento de los datos, mediante el análisis de los paradatos y microdatos del Censo Demográfico brasileño de 2010. Los paradatos se refieren a informaciones sobre la operación de relevamiento y la administración de la investigación originarias, respectivamente, del sistema de gestión de recursos humanos del personal dedicado a la recogida y del sistema de supervisión de la operación de recolección. Este estudio analizó las divergencias observadas entre las informaciones recogidas por los encuestadores y las informaciones obtenidas por los supervisores en las reentrevistas de los procedimientos de supervisión del trabajo de campo. Para el análisis de las divergencias entre informaciones recogidas por los encuestadores y supervisores se utilizaron modelos jerárquicos generalizados. El estudio muestra que hay diferencias en las discordancias asociadas con la estructura de relevamiento de los datos, con las características de los encuestadores, supervisores e informantes, y revelan diferencias regionales. Queda evidente, sobretodo, una fuerte influencia de las características del informante en las posibilidades de ocurrencia de divergencias, en detrimento a las características de los supervisores y encuestadores. Los resultados del modelo estadístico sugieren que las entrevistas realizadas con informantes del sexo masculino, analfabetos o con bajo nivel educativo, mayores y que viven en hogares con indicadores que reflejan condiciones de vida menos satisfactorias, presentan chances adicionales en favor de la ocurrencia de divergencia entre las respuestas recogidas por el encuestador y el supervisor.

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Se usó un diseño cuasi-experimental con pre y post-test para estimar el efecto de una capacitación para la prueba de admisión de la Universidad Costa Rica, un test estandarizado que mide habilidades de razonamiento en contextos verbales y matemáticos. Cuatro colegios públicos del área metropolitana central del país participaron en el estudio, asignándose dos de ellos aleatoriamente al grupo de intervención y los otros dos al grupo de control, con 61 estudiantes en el primer grupo y 80 en el segundo. La intervención consistió de 5 sesiones de capacitación de 3 horas, utilizando como guía un manual desarrollado por una experta pedagoga, con enfoque constructivista. Las medidas antes y después fueron formas reducidas de la prueba de admisión 2014. La variable dependiente fue la diferencia entre ambas mediciones. El efecto de la capacitación fue de 3.5 puntos porcentuales y significativo, y se estimó utilizando un modelo bayesiano de regresión multinivel.

A quasi-experimental design with pre and post- test was used to estimate training effects for the University of Costa Rica's admission test, a standardized exam that measures reasoning abilities in mathematical and verbal contexts. Four secondary public schools from the metropolitan central area of the country participated in the study; two of them were randomly assigned to the intervention group and the other two to the control group, with 61 students in the first group and 80 in the second. The intervention consisted of five three-hour training sessions, using a written guide developed by a pedagogy expert with a constructivist approach. Before and after measures were reduced test forms of the real admission test from the year 2014. The dependent variable was the difference between the two measures. The effect of the training was estimated using a multilevel Bayesian regression model with a significant magnitude of 3.5 percentage points.

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We organize our behavior and store structured information with many procedures that require the coding of spatial and temporal order in specific neural modules. In the simplest cases, spatial and temporal relations are condensed in prepositions like "below" and "above", "behind" and "in front of", or "before" and "after", etc. Neural operators lie beneath these words, sharing some similarities with logical gates that compute spatial and temporal asymmetric relations. We show how these operators can be modeled by means of neural matrix memories acting on Kronecker tensor products of vectors. The complexity of these memories is further enhanced by their ability to store episodes unfolding in space and time. How does the brain scale up from the raw plasticity of contingent episodic memories to the apparent stable connectivity of large neural networks? We clarify this transition by analyzing a model that flexibly codes episodic spatial and temporal structures into contextual markers capable of linking different memory modules.

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OBJECTIVE: To describe the distribution of alcohol-attributable mortality (AAM) at the local level (345 municipalities) in Chile, including fully and partially attributable causes in 2009. METHODS: AAM was estimated for the population 15years of age and older using per capita alcohol consumption combined with survey estimates. The effect of alcohol on each cause of death was extracted from the published scientific literature. We used Bayesian hierarchical models to smooth the Standardized Mortality Ratio for each municipality for six groups of causes related to alcohol consumption (total, neuro-psychiatric, cardiovascular, cancer, injuries and other causes). RESULTS: The percentage of municipalities with high risk for any group of causes in each region ranges from 0% to 87.0%. Municipalities with high risk were concentrated in south-central and southern Chile for all groups of causes related to alcohol. CONCLUSIONS: AAM risk shows marked geographic concentrations, mainly in south-central and southern regions of Chile. This combination of methods for small-area estimates of AAM is a powerful tool to identify high risk regions and associated factors, and may be used to inform local policies and programs.

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O presente estudo está inserido na linha dos trabalhos que buscam compreender os diferentes fatores que influenciam o funcionamento das escolas da rede pública de ensino brasileira, bem como a sua qualidade, a partir da identificação de variáveis que impactam os resultados escolares, em particular o desempenho dos alunos medido pelos sistemas de avaliação utilizados pelo Inep/MEC. Os fatores que influenciam a proficiência são múltiplos e complexos, contemplando dinâmicas que atuam em diferentes níveis, desde o mais elementar, das características socioeconômicas e culturais dos indivíduos e de suas famílias, até as dinâmicas que ocorrem nas salas de aula, entre professores e alunos, e as características estruturais da escola. Alunos e seus responsáveis, diretores e professores das instituições de ensino são alguns dos atores relevantes que agem sobre o processo latente gerador de maiores ou menores rendimentos escolares. Mais especificamente, o objetivo do presente estudo é analisar os possíveis fatores que influenciam o desempenho escolar dos alunos do 5º ano do ensino fundamental, nas escolas públicas municipais da cidade do Rio de Janeiro. Para tanto, foram utilizados modelos hierárquicos com três níveis, que permitiram avaliar os efeitos de variáveis socioeconômicas e culturais e dos contextos familiares dos alunos, de práticas pedagógicas e estilos de ensinar dos docentes e, ainda, de políticas educacionais, aspectos da gestão e características das escolas. O estudo teve como fonte principal as informações provenientes da Prova Brasil 2007.

This study is included in the line of research which seeks to identify different factors that influence the operation of public schools and their quality by identifying variables that affect educational outcomes, in particular, students' achievements measured by educational assessment procedures conducted by the Instituto Nacional de Estudos e Pesquisas Educacionais Anísio Teixeira (Inep/MEC). Factors that influence students' proficiency are numerous and complex, and include dynamics operating on different levels, from socioeconomic and cultural features of individuals and their families, through the dynamics that take place in classrooms between teachers and students, and extending to structural features of schools. Significant actors that explain better or weaker student outcomes include students themselves as well as their relatives, school employees, principals and teachers . The objective of this study was to analyze the possible factors that influence the educational achievements of students in the fifth year of public elementary schools in the city of Rio de Janeiro. For this purpose, three-level hierarchical linear models were used to assess the effects of socioeconomic, cultural and family backgrounds of students, teaching practices and styles, and even educational policies, management aspects and other features of schools. The primary data source was Prova Brasil 2007.

Este estudio se inserta en la línea de los trabajos que buscan comprender los diferentes factores que influyen en el funcionamiento y la calidad de las escuelas de la red de educación pública brasileña a partir de la identificación de las variables que impactan en los resultados escolares, en particular el desempeño de los alumnos medido por los sistemas de evaluación utilizados por el Instituto Nacional de Estudos e Pesquisas Educacionais Anísio Teixeira (Inep/MEC). Los factores que influyen en el nivel de competencia son múltiples y complejos, y abarcan dinámicas que operan en diferentes niveles, desde los más elementales, como las características socioeconómicas y culturales de los individuos y sus familias, hasta las dinámicas que se producen en las aulas, entre los profesores y los alumnos, y las características estructurales de la escuela. Los alumnos y sus padres, los directores y los profesores de las instituciones educativas son algunos de los actores relevantes que actúan sobre el proceso latente generador de mayores o menores rendimientos escolares. Más específicamente, el objetivo de este estudio es analizar los posibles factores que influyen en el desempeño escolar de los estudiantes del quinto año de la enseñanza básica en las escuelas públicas municipales de la ciudad de Río de Janeiro. Para ello se utilizaron modelos jerárquicos con tres niveles, lo que permitió evaluar los efectos de las variables socioeconómicas y culturales y de los contextos familiares de los alumnos, las prácticas pedagógicas y los estilos de enseñanza de los docentes y también de las políticas educativas, los aspectos de gestión y características de las escuelas. La principal fuente de información del estudio fueron los datos de la Prueba Brasil 2007.

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BACKGROUND: Little is known about the association between alcohol-attributable mortality and small area socioeconomic variables when considering causes both wholly and partially attributable to alcohol. METHODS: An ecological study was conducted of the entire Chilean population aged 15 and older in 345 municipalities nationwide between 2004 and 2009. Deaths were attributed to alcohol consumption either wholly or partially, along with the estimated attributable fractions for each specified cause. Each municipality was characterized according to its average income and educational attainment. Estimates of the ecological associations were produced using a hierarchical Bayesian model, separating out deaths caused by alcohol and dividing them into seven groups of causes. RESULTS: Alcohol-attributable mortality risk showed an inverse association with income and education at the ecological level. A one-quintile increase in income was associated with an average decrease in risk of 10% (CI 95%: 10-20%) for cardiovascular deaths, 8% (6-10%) for intentional injuries and 7% (3-11%) for unintentional injuries. No associations were found between deaths due to cancers and other causes with income and education. CONCLUSIONS: Municipalities with lower income and education have higher risk of alcohol-attributable mortality in Chile.

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Zero-inflated counting data of juvenile blue crabs (Callinectes sapidus Rathbun, 1896) collected in two estuaries of Rio Grande do Sul are the object of the present study. These data led to the formulation of hierarchical models that quantify the effect of categorical covariates months and location on the probability of occurrence and density of these populations, taking imperfect detection into account. Nonhierarchical models were also developed for comparison. A Bayesian approach was adopted for estimating model parameters using the Markov Chain Monte Carlo (MCMC) simulation technique. Model comparison was performed according to the Deviance Information Criterion (DIC). Hierarchical models resulted in better fits than conventional ones, mitigated the problem of excess zeros and allowed for simultaneous analysis of the probability of occurrence and the density of juvenile blue crab. The probability of occurrence of Class 2 juveniles in the Lagoa dos Patos estuary increases at larger distance from the mouth while in Tramandaí the occurrence is more likely for intermediate distances. In both estuaries the occurrence is more likely in the summer and winter months. Regarding density of Class 2 juveniles, there is marked variation among the months of the year; and is overall higher in the Tramandaí estuary.(AU)

Dados de contagem de juvenis de siri-azul (Callinectes sapidus Rathbun, 1896) coletados em dois estuários do Rio Grande do Sul são objeto do presente estudo. Por se encontrarem zero-inflacionados, esses dados motivaram a formulação de modelos hierárquicos, que quantificam o efeito das covariáveis categóricas mês e local sobre a probabilidade de ocorrência e densidade dessas populações, levando em conta a detecção imperfeita. Foram também desenvolvidos modelos não-hierárquicos para comparação. Uma abordagem Bayesiana foi adotada para a estimação dos parâmetros dos modelos por simulação Monte Carlo com Cadeias de Markov (MCMC). A comparação entre modelos foi feita com o Critério de Informação da Deviância (DIC). Os modelos hierárquicos apresentaram ajustes melhores que os modelos convencionais, mitigaram o problema do excesso de zeros e permitiram analisar simultaneamente as probabilidades de ocorrência e a densidade de juvenis de siri-azul. No estuário da Lagoa dos Patos, a probabilidade de ocorrência de juvenis na Classe 2 aumenta com a distância da desembocadura, enquanto em Tramandaí os pontos intermediários apresentam as maiores probabilidades. Em ambos os estuários a ocorrência é mais provável nos meses de verão e de inverno. A densidade de juvenis da Classe 2 apresenta marcada variação em relação aos meses do ano sendo, em geral, maior no estuário de Tramandaí.(AU)

Assuntos

RESUMO

Zero-inflated counting data of juvenile blue crabs (Callinectes sapidus Rathbun, 1896) collected in two estuaries of Rio Grande do Sul are the object of the present study. These data led to the formulation of hierarchical models that quantify the effect of categorical covariates months and location on the probability of occurrence and density of these populations, taking imperfect detection into account. Nonhierarchical models were also developed for comparison. A Bayesian approach was adopted for estimating model parameters using the Markov Chain Monte Carlo (MCMC) simulation technique. Model comparison was performed according to the Deviance Information Criterion (DIC). Hierarchical models resulted in better fits than conventional ones, mitigated the problem of excess zeros and allowed for simultaneous analysis of the probability of occurrence and the density of juvenile blue crab. The probability of occurrence of Class 2 juveniles in the Lagoa dos Patos estuary increases at larger distance from the mouth while in Tramandaí the occurrence is more likely for intermediate distances. In both estuaries the occurrence is more likely in the summer and winter months. Regarding density of Class 2 juveniles, there is marked variation among the months of the year; and is overall higher in the Tramandaí estuary.

Dados de contagem de juvenis de siri-azul (Callinectes sapidus Rathbun, 1896) coletados em dois estuários do Rio Grande do Sul são objeto do presente estudo. Por se encontrarem zero-inflacionados, esses dados motivaram a formulação de modelos hierárquicos, que quantificam o efeito das covariáveis categóricas mês e local sobre a probabilidade de ocorrência e densidade dessas populações, levando em conta a detecção imperfeita. Foram também desenvolvidos modelos não-hierárquicos para comparação. Uma abordagem Bayesiana foi adotada para a estimação dos parâmetros dos modelos por simulação Monte Carlo com Cadeias de Markov (MCMC). A comparação entre modelos foi feita com o Critério de Informação da Deviância (DIC). Os modelos hierárquicos apresentaram ajustes melhores que os modelos convencionais, mitigaram o problema do excesso de zeros e permitiram analisar simultaneamente as probabilidades de ocorrência e a densidade de juvenis de siri-azul. No estuário da Lagoa dos Patos, a probabilidade de ocorrência de juvenis na Classe 2 aumenta com a distância da desembocadura, enquanto em Tramandaí os pontos intermediários apresentam as maiores probabilidades. Em ambos os estuários a ocorrência é mais provável nos meses de verão e de inverno. A densidade de juvenis da Classe 2 apresenta marcada variação em relação aos meses do ano sendo, em geral, maior no estuário de Tramandaí.

Assuntos

RESUMO

Los modelos Bayesianos jerárquicos espaciotemporales han sido usados en el mapeo de enfermedades, estudios de contaminación ambiental, contaminación industrial, entre muchos otros. Bajo esta metodología, los datos están asociados con un punto en una localidad E y con un instante de tiempo t. El objetivo de este trabajo es modelar el riesgo relativo de contraer dengue en el municipio Girardot del estado Aragua, Venezuela, durante el periodo epidemiológico del año 2009. Se proponen tres estructuras de modelos, un Binomial que toma en cuenta la variabilidad en el conteo de la ocurrencia de la enfermedad en las parroquias del municipio. Una segunda propuesta incluye un modelo Binomial como primer nivel de jerarquía, más un segundo nivel que introduce el efecto espacial, el efecto temporal y la interacción espacio-tiempo. Finalmente, un tercer modelo espacial que combina el modelo Poisson en el primer nivel de jerarquía para el número de casos, y en el segundo nivel de jerarquía se relaciona el riesgo relativo con las covariables a través de la función logaritmo más un efecto aleatorio. Los datos fueron recopilados por semanas y clasificados de acuerdo a las parroquias del municipio. Se utilizó el criterio de información de deviancia (DIC) para seleccionar el mejor modelo, resultando el modelo Poisson el más adecuado para representar el riesgo relativo de contraer dengue en la zona bajo estudio, confirmando que los patrones de alto riesgo se encuentran en las parroquias ubicadas al sur y suroeste del municipio Girardot, colindando algunas de ellas con el lago de Valencia.

Hierarchical Bayesian space-time models have been used in the mapping of disease, studies of environmental pollution and industrial pollution, among many others. Under this methodology, the data is associated with point in a locality E and an instant in time t. The aim of this work is to model the relative risk of dengue in Girardot Municipality, Aragua State, Venezuela, during the epidemic period 2009. In that sense, we propose three models. First, a binomial model that measures the variability in the count of occurrence of the disease in the parishes of the municipality. A second model includes the binomial model as a first hierarchical level, plus a second level which introduces the spatial effect, the temporal effect and spacetime interaction. Finally, a third spatial model that follows a Poisson model at the first level of hierarchy for the number of cases, and in the second level of hierarchy relates the relative risk associated with covariates through the logarithm function over a random effect. Data were collected for weeks and classified according to the parishes of the municipality. The Deviance Information Criterion (DIC) was used to select the best model. The Poisson model was best suited to represent the relative risk of contracting dengue in the area under study, showing that high-risk patterns were found in the parishes located in the south and southwest of the Girardot municipality, some of them bordering the lake of Valencia.

Assuntos