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61.
Quantile regression models are a powerful tool for studying different points of the conditional distribution of univariate response variables. Their multivariate counterpart extension though is not straightforward, starting with the definition of multivariate quantiles. We propose here a flexible Bayesian quantile regression model when the response variable is multivariate, where we are able to define a structured additive framework for all predictor variables. We build on previous ideas considering a directional approach to define the quantiles of a response variable with multiple outputs, and we define noncrossing quantiles in every directional quantile model. We define a Markov chain Monte Carlo (MCMC) procedure for model estimation, where the noncrossing property is obtained considering a Gaussian process design to model the correlation between several quantile regression models. We illustrate the results of these models using two datasets: one on dimensions of inequality in the population, such as income and health; the second on scores of students in the Brazilian High School National Exam, considering three dimensions for the response variable.  相似文献   
62.

This article advances theory on social movements’ strategic adaptation to political opportunity structures by incorporating a narrative perspective. Our theory explains how people acquire and use knowledge about political opportunity structures through storytelling about the movement’s past, present, and imagined future. The discussion applies the theory in an ethnographic case study of the climate movement’s mobilization around the UN Climate Summit in Paris, 2015. This analysis demonstrates how a dominant narrative of defeat about the prior protest campaign in Copenhagen, 2009 shaped the strategizing process. While those who experienced Copenhagen as a success preferred strategic continuity, those who experienced defeat developed a “Copenhagen narrative” to advance strategic adaptation by projecting previously experienced threats and opportunities onto the Paris campaign. Yet by relying on a retrospective narrative, movement actors tended to overlook emerging political opportunities. We demonstrate that narrative analysis is a useful tool for understanding the link between structure and agency in social movements and other actors affected by (political) opportunity structures.

  相似文献   
63.
The analysis of risk-return tradeoffs and their practical applications to portfolio analysis paved the way for Modern Portfolio Theory (MPT), which won Harry Markowitz a 1992 Nobel Prize in Economics. A typical approach in measuring a portfolio's expected return is based on the historical returns of the assets included in a portfolio. On the other hand, portfolio risk is usually measured using volatility, which is derived from the historical variance-covariance relationships among the portfolio assets. This article focuses on assessing portfolio risk, with emphasis on extreme risks. To date, volatility is a major measure of risk owing to its simplicity and validity for relatively small asset price fluctuations. Volatility is a justified measure for stable market performance, but it is weak in addressing portfolio risk under aberrant market fluctuations. Extreme market crashes such as that on October 19, 1987 ("Black Monday") and catastrophic events such as the terrorist attack of September 11, 2001 that led to a four-day suspension of trading on the New York Stock Exchange (NYSE) are a few examples where measuring risk via volatility can lead to inaccurate predictions. Thus, there is a need for a more robust metric of risk. By invoking the principles of the extreme-risk-analysis method through the partitioned multiobjective risk method (PMRM), this article contributes to the modeling of extreme risks in portfolio performance. A measure of an extreme portfolio risk, denoted by f(4), is defined as the conditional expectation for a lower-tail region of the distribution of the possible portfolio returns. This article presents a multiobjective problem formulation consisting of optimizing expected return and f(4), whose solution is determined using Evolver-a software that implements a genetic algorithm. Under business-as-usual market scenarios, the results of the proposed PMRM portfolio selection model are found to be compatible with those of the volatility-based model. However, under extremely unfavorable market conditions, results indicate that f(4) can be a more valid measure of risk than volatility.  相似文献   
64.

Introduction

The following quantitative observational study aimed to analyse the maternal and neonatal outcomes of 90 low-risk pregnant women who gave birth in water at São Bernardo Hospital.

Methods

A form containing information on the obstetric history of the parturient, the type of immersion, and the labour and birth follow-up was used by midwives to collect the data.

Background

The Apgar score (at 1 min after birth) used in this study, called Aqua Apgar, was adapted by Cornelia Enning.

Results

The mean water immersion time was 1 h and 46 min and had an influence on the duration of labour (mean 5 h and 37 min), with a statistically significant difference (P = 0.004). There was a decreased cervical dilatation time and a shorter duration of the expulsion phase. In the immersion scenario, 30% of the women did not undergo any examination to assess the length of the cervix, and 57.8% presented intact perennial areas or first-degree tears. As for neonatal outcomes, during maternal immersion, 97% maintained normal fetal heart rates (between 110 and 160 beats per minute) and Aqua Apgar was higher than 7, both in the first minute (mean of 9.4) and in the fifth minute of life (mean of 9.9).

Conclusion

These safety outcomes, based on sound scientific evidence, should increasingly support and inform clinical decisions and increase the number of waterbirths in health facilities. The results of this study align with growing evidence that suggests waterbirth is a safe delivery option and therefore should be offered to women.  相似文献   
65.
This essay aims to reflect on the idea of landscape and our relationship with it by taking the Japanese notion of furusato (native place) in its ontological dimension. Grounded in Heidegger’s ‘phenomenology of Being’ and ‘ontology’, a phenomenological understanding of fieldwork experience in a Japanese rural community will be developed in order to rethink both the furusato and the ‘Being-landscape’ relation. As a consequence, we will be concerned not with how people speak about landscape, but with how the landscape speaks through people. What will be brought to light are the landscape’s moral and relational dimensions: namely, (i) the responsibility towards both our communities and future generations and (ii) a more-than-physical understanding of landscape that alerts us to our belonging to a common world comprised of relationships and tasks.  相似文献   
66.
This study is aimed at the effects of making apologies in a crisis situation and attributed crisis responsibility on corporate- and spokesperson reputation. In a 2 × 2 scenario experiment (spokesperson making apologies versus no apologies; and accidental versus preventable crisis), 84 respondents judged corporate and spokesperson reputation. We found that the crisis has more impact on corporate reputation than on the spokesperson's reputation. This indicates that the crisis is seen as a collective responsibility of the organization, rather than the personal responsibility of the spokesperson.  相似文献   
67.
The aim of the present study is to contribute to the analysis of employment and work conditions of Portuguese trainers, as well as to identify conditions, resources, demands and constraints of their work activities. Despite the lack of scientific knowledge on professional training, the topic has been playing a central role in modern societies. Several data collection strategies were used, namely the application of INSAT to 72 trainers, exploratory interviews with 10 trainers and collective interviews with 6 trainers. The analysis of the data collected highlights the changes in the selection of human resources in the sector as well as the contractual terms of the trainers, mainly independent workers. The intra and inter individual variability of working hours and the diversity of activities performed by each trainer also stands out. Finally, it is important to refer the spontaneous organization of trainers' work activities according to their training modality.  相似文献   
68.
The generation growing and diversified of Municipal Solid Waste is configured as an environmental problem, economic and social deterioration, especially, by application of inappropriate management of them. Faced with this urban context, the research in development presents as specific objective assessment of the quality of life of the gatherers of recyclable materials were active in the city of Juiz de Fora, in the brazilian state of Minas Gerais. In addition, the objective is, still, the recognition of the activity of sorting performed by "scavengers" in order to maximize the reduction, reuse and recycling energy and material waste daily. The proposed methodology is based on the application of the questionnaire Word Health Organization Quality of Life (WHOQOL-100), prepared by the World Health Organization, in order to value the quality of life of the gatherers of recyclable materials, involved, even in educational workshops in order to discuss and organize strategies of health care and scouting to the basement to public policies.  相似文献   
69.
This paper will present the workflow developed for the application of serious games in the design of complex cooperative work settings. The project was based on ergonomic studies and development of a control room among participative design process. Our main concerns were the 3D human virtual representation acquired from 3D scanning, human interaction, workspace layout and equipment designed considering ergonomics standards. Using Unity3D platform to design the virtual environment, the virtual human model can be controlled by users on dynamic scenario in order to evaluate the new work settings and simulate work activities. The results obtained showed that this virtual technology can drastically change the design process by improving the level of interaction between final users and, managers and human factors team.  相似文献   
70.
Following a research carried out on the integration of women in professional areas predominantly for men, this paper intends to present and debate the project of a training course which aims the transformation of the organization of work schedules in order to improve the well-being of the workers involved. The conception of training courses with this type of objective involves the confrontation and debate between the "invested skills" of the trainers and the "constituted skills" of the trainees. But will this paradigm remain intact when applied to training courses permeated by the gender dimension? That is what one will try to realize with the effective implementation of a training course, whose reflection will allow, ultimately, to enrich our understanding on gender, work, health and training.  相似文献   
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