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211.
In this paper considering an appropriate transformation on the Lindley distribution, we propose the unit-Lindley distribution and investigate some of its statistical properties. An important fact associated with this new distribution is that it is possible to obtain the analytical expression for bias correction of the maximum likelihood estimator. Moreover, it belongs to the exponential family. This distribution allows us to incorporate covariates directly in the mean and consequently to quantify their influences on the average of the response variable. Finally, a practical application is presented to show that our model fits much better than the Beta regression.  相似文献   
212.
A previously known result in the econometrics literature is that when covariates of an underlying data generating process are jointly normally distributed, estimates from a nonlinear model that is misspecified as linear can be interpreted as average marginal effects. This has been shown for models with exogenous covariates and separability between covariates and errors. In this paper, we extend this identification result to a variety of more general cases, in particular for combinations of separable and nonseparable models under both exogeneity and endogeneity. So long as the underlying model belongs to one of these large classes of data generating processes, our results show that nothing else must be known about the true DGP—beyond normality of observable data, a testable assumption—in order for linear estimators to be interpretable as average marginal effects. We use simulation to explore the performance of these estimators using a misspecified linear model and show they perform well when the data are normal but can perform poorly when this is not the case.  相似文献   
213.
We introduce a Bayesian instrumental variable procedure with spatial random effects that handles endogeneity, and spatial dependence with unobserved heterogeneity. We find through a limited Monte Carlo experiment that our proposal works well in terms of point estimates and prediction. We apply our method to analyze the welfare effects generated by a process of electricity tariff unification on the poorest households. In particular, we deduce an Equivalent Variation measure where there is a budget constraint for a two-tiered pricing scheme, and find that 10% of the poorest municipalities attained welfare gains above 2% of their initial income.  相似文献   
214.
Self-efficacy beliefs are central to mental health. Because adolescents' neighborhoods shape opportunities for experiences of control, predictability, and safety, we propose that neighborhood conditions are associated with adolescents' self-efficacy and, in turn, their internalizing problems (i.e., depression/anxiety symptoms). We tested these hypotheses using three waves of data from the Project on Human Development in Chicago Neighborhoods (N = 2,345). Results indicate that adolescents living in violent neighborhoods tended to report lower self-efficacy beliefs, partly because they were more likely to experience fear in their neighborhood. However, moving out of Chicago neighborhoods marked by violence and low collective efficacy to neighborhoods outside of the city was associated with adolescents' increased self-efficacy (vs. staying in such neighborhoods), an association explained by adolescents' school-related experiences. Finally, through self-efficacy, these neighborhood processes had an indirect association with adolescents' internalizing problems. Results partially support a model linking neighborhood conditions, cognitions about the self, and emotions.  相似文献   
215.
The historic cities of Brazil, despite its colonial structure, don't fail to go through transformations that affect contemporary cities, which is the main source of problems, leading to new approaches to urban issues such as mobility and accessibility. The uncontrolled growth of tourism in the historic cities can be considered as a big problem, because at the same time, they have committed to the conservation of its built heritage and demand control of the activities that occur in their areas without harm. Then, a permanent dialogue between conservatives and planners could be accomplished by joining the various sectoral policies. The study of urban mobility in historical sites was in fact the focus of this work because of their peculiarities, such as its specific characteristics of urban structure, morphology and occupation. In fact, the development of tourism in historic centers generates specific demands, such as adaptation to new uses of the houses, intensive movement of people and vehicles, illegal parking, among others. Beyond threatening the city preservation, does not provide mobility and accessibility to tourists, because these cities were not designed for the tourism conditions and needs of contemporary life. Characteristic features of Brazilian baroque cities, such as topography , the narrow streets, narrow or nonexistent sidewalks, steep turns and ramps strong, are not suitable for heavy vehicles, traffic and pedestrian circulation. Thus, studies concerning conservation urban integrated are aimed at an approach to interaction between historic preservation of the environment with the dynamic socio-economic of the local.  相似文献   
216.
In the workplace there are risk factors that can overwhelm the health of the worker causing physical and psychological disorders. Among these disorders, is occupational stress. Thus, this research proposes to measure the mental workload of job stress from the identification of demand, control and social support. It is an observational cross-sectional epidemiological character, performed with the Rectory office workers at the State University of West Paraná (Unioeste). Data collection was due to the application of the "Job Stress Scale" (JSS) and in its reduced version adapted to Portuguese. The survey sample consisted of 44 individuals. Statistical analysis was correlated inversely with medium intensity (r = -0.404) between age and social support. For males was found between control and age (r = 0.603). According to the data obtained, we conclude that most workers are exposed to passive work, leading to loss of skills or disinterest in the job. This study highlights the importance of research in the area and the need for new actions that change the conditions of stress at work.  相似文献   
217.
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   
218.
Contemporary electronic industry offers a wide range of products. Usually touch sensitive and with few buttons and a lot of functions these products not always have a friendly interface. The human x design interface based on electronics' ergonomics is the focus of this research. An evolutionary analysis of the electronics industry design within a contemporary context clarifies this relation and proposes new guidelines for a more conscious design.  相似文献   
219.
Blomé M  Ek A 《Work (Reading, Mass.)》2012,41(Z1):3213-3215
To be able to disseminate knowledge about maritime safety culture and safety management to different actors in the Swedish maritime sector, a preliminary pedagogical concept was developed and evaluated. As a first user group, students at upper secondary maritime schools were chosen and the pedagogical concept was adapted for this group. The concept includes an interactive prototype and a teacher's guide and is based on a model for experience-based learning which connects theory and practice by a cyclic approach. The concept was tested in a classroom setting including interaction with the students and a follow-up one week later. A preliminary evaluation of the results shows a very positive response among the students as well as the lecturers. The educational material was successful in immediately creating a relevant discussion about safety culture, and one week later, students could remember many of the safety scenarios included in the pedagogical concept.  相似文献   
220.
To cut a fabric, the professional performs different jobs and among them stands out the cut. The scissors has been the instrument most used for this activity. Over the years, technology has been conquering its space in the textile industry. However, despite the industrial automation able to offer subsidies to answer employment market demands, without appropriate orientation, the worker is exposed to the risks inherent at the job. Ergonomics is a science that search to promote the comfort and well being in consonance with efficacy. Its goals are properly well defined and clearly guide the actions aimed at transforming the working conditions. This study aimed to analyze the activity of cut tissues with a machine by a seamstress and the implications on their body posture. The methodology used was the observation technique and application of the Protocol RULA, where the result obtained was the level 3 and score 5, confirming that "investigations and changes are required soon". Conclude that using the machine to tissue cut should be encouraged, but in conjunction with orientations for improving posture while handling it. It seeks to prevent dysfunction of the musculoskeletal system that prevents employees from performing their work tasks efficiently and productively.  相似文献   
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