排序方式: 共有43条查询结果,搜索用时 15 毫秒
31.
Emílio Augusto Coelho-Barros Jorge Alberto Achcar Josmar Mazucheli 《Journal of applied statistics》2010,37(5):865-880
In this paper, we present different “frailty” models to analyze longitudinal data in the presence of covariates. These models incorporate the extra-Poisson variability and the possible correlation among the repeated counting data for each individual. Assuming a CD4 counting data set in HIV-infected patients, we develop a hierarchical Bayesian analysis considering the different proposed models and using Markov Chain Monte Carlo methods. We also discuss some Bayesian discrimination aspects for the choice of the best model. 相似文献
32.
Mobile instant messaging services (MIMS) are emerging as important digital environments in citizens’ everyday lives. We explore the use of MIMS for talking about politics with unique survey data on samples representative of Internet users in Germany, Italy, and the UK. First, we show that robust percentages of our respondents who use MIMS employ them for posting political messages and discussing politics. Second, we demonstrate that political talk on MIMS is positively associated with users’ tendency to censor themselves politically on social networking sites (SNS) and, to a lesser extent, with ideological extremism. Third, we find that the association between self-censorship on SNS and the likelihood of publishing political contents on MIMS is stronger for individuals living in former East Germany where, due to historical reasons, large segments of the population are reluctant to talk about politics in public. Our findings suggest that MIMS make a distinctive contribution to contemporary repertoires of political talk, with important implications for the quality and inclusiveness of interpersonal political discussion. 相似文献
33.
Semiparametric Bayesian models are nowadays a popular tool in event history analysis. An important area of research concerns the investigation of frequentist properties of posterior inference. In this paper, we propose novel semiparametric Bayesian models for the analysis of competing risks data and investigate the Bernstein–von Mises theorem for differentiable functionals of model parameters. The model is specified by expressing the cause-specific hazard as the product of the conditional probability of a failure type and the overall hazard rate. We take the conditional probability as a smooth function of time and leave the cumulative overall hazard unspecified. A prior distribution is defined on the joint parameter space, which includes a beta process prior for the cumulative overall hazard. We first develop the large-sample properties of maximum likelihood estimators by giving simple sufficient conditions for them to hold. Then, we show that, under the chosen priors, the posterior distribution for any differentiable functional of interest is asymptotically equivalent to the sampling distribution derived from maximum likelihood estimation. A simulation study is provided to illustrate the coverage properties of credible intervals on cumulative incidence functions. 相似文献
34.
Snia Goulart Cardoso Mnica Truninger Vasco Ramos Fbio Rafael Augusto 《Children & Society》2019,33(6):572-586
This paper addresses the importance of school meals in balancing food budgets and diets among 45 low‐income families in Portugal. Drawing on interviews with both parents and children (aged 11–15 years) we found that children’s views on the quality of school meals affect their willingness to eat at school and heighten parental concerns with health, food and resources. For parents, school meals are crucial to ensure children’s dietary variety and balancing tight food budgets. Schools’ role in food poverty alleviation is also critically addressed, contributing to current and future sociological studies of children, school meals and food poverty. 相似文献
35.
Augusto Gnisci Ida Sergi Elvira De Luca Vanessa Errico 《Journal of Nonverbal Behavior》2012,36(1):39-57
The aim of this experiment was to determine if the frequency of interruptions during an interaction amplifies the effect of
the type of the interruptions on the interruptee (the amplification hypothesis). While interviewing 90 participants, two confederates
manipulated four different kinds of interruptions (change-subject, same-subject, disagreement, and supportive interruptions)
at two different frequencies (mean rates, 1.58 and 2.94 per minute), in addition to a no-interruption control condition. At
the end of the interview, the participants were asked to answer questions about themselves, the interlocutor, and the situation.
The results showed that the negative effects of change- and same-subject interruptions were amplified when they were more
frequent, as were the positive effects of supportive interruptions. Contrary to expectations, disagreement interruptions were
regarded as positive. All the results provide support for the amplification hypothesis. 相似文献
36.
The aim of this study was to evaluate factors associated with reported work-related musculoskeletal symptoms among aircraft assembly workers. Population consisted of 552 (491 men/61 women) workers who performed tasks related to the work of aircraft assembly. Participants completed a comprehensive questionnaire, including socio-demographic information, habits/lifestyles, working conditions, and work organization. Workers also answered the Nordic Musculoskeletal Questionnaire to obtain data on musculoskeletal symptoms. Multivariate logistic regression was performed to analyze factors associated with musculoskeletal reported symptoms. Results showed that body regions with the highest prevalence of reported musculoskeletal symptoms were similar when referred the past twelve months and the past seven days. Significant factors associated with musculoskeletal symptoms included variables related to conflicts at work, sleep problems, mental fatigue, and lack of time for personal care and recovery. Working time in the industry was associated only with reports for the last seven days and regular physical activity off-work seems to be a positive factor in preventing musculoskeletal symptoms for the past twelve months. The results highlight the multi-factorial nature of the problem. Actions to prevent musculoskeletal diseases at the aircraft assembly work should consider multiple interventions that would promote better recovery between work shifts. 相似文献
37.
This paper aims to demonstrate the situation of the buildings declared a historical landmark by the government spheres in the state of Pernambuco, and how they attend the norms of accessibility for those with special needs. The methodology of the research contemplated a sample of 46 heritage buildings, approximately 16% of the universe of properties, which are around 268. In turn, these were limited to Recife's Metropolitan Region Area - RMR comprising 30% of the 153 properties of the municipalities of: Cabo de Santo Agostinho, Igarassu, Itamaracá, Ipojuca, Jaboat?o dos Guararapes, Moreno, Olinda, Paulista, Recife and S?o Louren?o da Mata. From the specific forms set up based on the theoretical reference, as well as graphics and photographic records were assessed the aspects of both internal and external accessibility, displacement, (visual) orientation, and the use of space and equipment. In the analysis of different types was assembled a summary table ranking the samples in accessible, partially accessible and not accessible. As general results were found that from the 46 properties examined, 2 (5%) are accessible, 16 (35%) are partially accessible and 28(60%) are not accessible. Such data, although sample, shows that the majority of heritage properties does not provide access to people physically disabled or with reduced mobility signaling for professionals, managers and society institutions on the need to reduce physical barriers in such heritage. 相似文献
38.
Magda Carvalho Pires Enrico Antnio Colosimo Guilherme Augusto Veloso Raquel de Souza Borges Ferreira 《Journal of applied statistics》2021,48(5):907
Survival data involving silent events are often subject to interval censoring (the event is known to occur within a time interval) and classification errors if a test with no perfect sensitivity and specificity is applied. Considering the nature of this data plays an important role in estimating the time distribution until the occurrence of the event. In this context, we incorporate validation subsets into the parametric proportional hazard model, and show that this additional data, combined with Bayesian inference, compensate the lack of knowledge about test sensitivity and specificity improving the parameter estimates. The proposed model is evaluated through simulation studies, and Bayesian analysis is conducted within a Gibbs sampling procedure. The posterior estimates obtained under validation subset models present lower bias and standard deviation compared to the scenario with no validation subset or the model that assumes perfect sensitivity and specificity. Finally, we illustrate the usefulness of the new methodology with an analysis of real data about HIV acquisition in female sex workers that have been discussed in the literature. 相似文献
39.
Time is a fundamental instrument of orientation for social life, and it is closely intertwined with both public and private spaces and the resources contained therein. The aim of this study is to describe and analyse the organization of daily life among women with disabilities in Belo Horizonte, Brazil, from the perspective of temporality. Results were obtained by a combination of quantitative and qualitative methods, using a sample of 50 women with physical/motor disabilities. They self-reported difficulties when walking and/or climbing stairs. The analysis of time use by individuals with disabilities revealed six main types of activities associated with daily life: personal care, paid work, studying, housework, free time, and travelling from one place to another. The results reveal that although the daily lives of these women are hampered by their functional limitations, their lives are also directly influenced by their physical and social contexts and their attitudes. 相似文献
40.
Emanuele Blasi Maria Nucera Clara Cicatiello Silvio Franco 《Social indicators research》2013,113(1):451-470
This work is part of a well-established strand of study about quality of life (QoL) and the different methodologies for its quantitative evaluation. The study focuses on a specific dimension of QoL, that of the eudaimonic well-being (EuWB), with two main objectives. On the one hand, we try to clarify how EuWB can be framed in the systematizations of QoL proposed in the literature. Its relation to the concept of subjective well-being is discussed, and the need to distinguish such approach from the so-called hedonic dimension of QoL is highlighted. On the other hand, the paper aims to investigate the link between the perception of EuWB and individual socio-demographic characteristics through a quantitative analysis based on the results of a survey. The survey carried out in Central Italy in 2010, involved a sample of 1,134 individuals, which are classified according to their perception of EuWB. An analysis of the socio-demographic characteristics within the EuWB groups is then performed in order to investigate the association between these variables and the perception of EuWB. Results are discussed with respect to the evidences from similar surveys found in the literature. The analysis confirms the influence of some variables on the perception of EuWB, yet it underlines the difficulty in comparing different studies on QoL without clarifying to which of the different declensions of this concept the survey methodology refers to. 相似文献