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401.
402.
George W. Leeson 《Journal of Population Research》2017,34(1):1-15
The world is ageing both at an individual and a population level, and population ageing is truly a global phenomenon. Life expectancies at birth have increased at the global level from 47 years in the mid-20th century to around 70 years today, and are expected to rise to 76 years by the mid-21st century. The proportion of the world’s population aged 60 years and over has increased from 8 % in the mid-20th century to 12 %, and by 2050 it is expected to reach 21 %. The emergence of large numbers of centenarians has accompanied this development. This paper outlines this emergence historically and the likely growth in the number of centenarians in the 21st century, in particular in England and Wales, analysing mortality trends since 1840 and the rise in the number of centenarians in the 20th and 21st centuries. The number of centenarians in England and Wales increased from around 160 in 1922 to almost 12,500 by 2012, but if mortality at all ages had remained constant from 1912 to 2012, then by 2012 the number of centenarians would only have been around 720. By 2100, the number of centenarians is expected to reach around 1.4 million, but if future mortality at all ages were to remain constant, then by 2100 the number of centenarians would be around 78,000. However, if predicted mortality for those aged 55 years and over was to decrease by an additional 5 % every 5 years until 2100, then the number of centenarians in England and Wales would reach around 1.8 million by the end of the century. 相似文献
403.
Francisco José López-Arceiz Ana José Bellostas María Pilar Rivera-Torres 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2017,28(4):1622-1647
The objective of this study is to analyze the aspects that allowed a critical part of Social Economy Organizations (SEOs) to survive a recession period, especially participation in collaborative networks. The financial stress of an SEO will depend on the resources and capabilities available to the organization. To analyze the financial stress of Spanish SEOs, we defined a sample of 714 SEOs. Approximately half of these organizations suffered from financial stress in the analyzed period (2009–2012). The results obtained in this study reveal the existence of three factors that distinguish organizations under financial stress: (a) a high dependence on government funding; (b) changes in the relationship between staff and volunteers; and (c) a lack of access to markets. The combination of these three elements results in an unsustainable situation for the organization. The development of a collaborative profile increases the SEO’s probability of surviving the adverse manifestations of its environment. 相似文献
404.
This paper explores the experiences of immigrant women with visual impairment in the Greater Toronto and Hamilton Area (GTHA) of Canada. Conceptually, the paper draws from feminist disability theory and critical scholarship on blindness to consider the discursive and material processes shaping women’s experiences across different socio-cultural contexts. Empirically, the paper draws from in-depth interviews with seven women. The analysis is organized around three themes. The first explores women’s understandings of visual impairment. The second examines the ways in which women’s experiences of visual impairment are shaped by meanings and attitudes that circulate within their cultural communities, and the extent to which immigration might challenge or reinforce these meanings. The third examines the shifting barriers and opportunities women face with respect to social and economic participation. We close by identifying the conceptual implications of our research. 相似文献
405.
Gavin A. Whitaker Andrew Golightly Richard J. Boys Chris Sherlock 《Statistics and Computing》2017,27(4):885-900
We consider the task of generating discrete-time realisations of a nonlinear multivariate diffusion process satisfying an Itô stochastic differential equation conditional on an observation taken at a fixed future time-point. Such realisations are typically termed diffusion bridges. Since, in general, no closed form expression exists for the transition densities of the process of interest, a widely adopted solution works with the Euler–Maruyama approximation, by replacing the intractable transition densities with Gaussian approximations. However, the density of the conditioned discrete-time process remains intractable, necessitating the use of computationally intensive methods such as Markov chain Monte Carlo. Designing an efficient proposal mechanism which can be applied to a noisy and partially observed system that exhibits nonlinear dynamics is a challenging problem, and is the focus of this paper. By partitioning the process into two parts, one that accounts for nonlinear dynamics in a deterministic way, and another as a residual stochastic process, we develop a class of novel constructs that bridge the residual process via a linear approximation. In addition, we adapt a recently proposed construct to a partial and noisy observation regime. We compare the performance of each new construct with a number of existing approaches, using three applications. 相似文献
406.
407.
A new numerical method to solve the downdating problem (and variants thereof), namely removing the effect of some observations from the generalized least squares (GLS) estimator of the general linear model (GLM) after it has been estimated, is extensively investigated. It is verified that the solution of the downdated least squares problem can be obtained from the estimation of an equivalent GLM, where the original model is updated with the imaginary deleted observations. This updated GLM has a non positive definite dispersion matrix which comprises complex covariance values and it is proved herein to yield the same normal equations as the downdated model. Additionally, the problem of deleting observations from the seemingly unrelated regressions model is addressed, demonstrating the direct applicability of this method to other multivariate linear models. The algorithms which implement the novel downdating method utilize efficiently the previous computations from the estimation of the original model. As a result, the computational cost is significantly reduced. This shows the great usability potential of the downdating method in computationally intensive problems. The downdating algorithms have been applied to real and synthetic data to illustrate their efficiency. 相似文献
408.
Racial/Ethnic Disparities in Mental Health Service Use for Older Foster Youth and Foster Care Alumni
Margarita Villagrana 《Child and Adolescent Social Work Journal》2017,34(5):419-429
Studies have shown that foster care alumni have disproportionally high rates of poor mental health outcomes compared to the general population. The purpose of this study was to examine differences in mental health service use for Latino, African American, and White youth while in foster care and upon exit from the foster care system. Secondary data were used to identify youth 1 year prior to exiting the foster care system (N?=?934) and 1 year after exit from the foster care system (N?=?433). Racial/ethnic disparities in mental health service use upon exit from the foster care system were found, with Latino youth using the least amount of services after foster care exit. Racial/ethnic service disparities in type of services used were also found. Findings suggest that a lack of support (e.g., mandatory or voluntary) may be significant in overcoming challenges in the continuation or disruption of services. 相似文献
409.
Heidi Möller 《Organisationsberatung, Supervision, Coaching》2017,24(2):127-130
410.
This paper investigates differential customer racial reaction to negative and positive publicity related to professional athletes. In terms of negative publicity, it analyzes the effect of mention in the Mitchell Report on the price of baseball cards. In regards to positive publicity, it considers the impact of having been identified as a member of the United States Olympic or national team. After controlling for player productivity with performance statistics, the effects of being mentioned in the Mitchell Report are isolated within regression analysis to draw conclusions concerning customer racial attitudes toward the steroids scandal. Similar analysis is conducted to see the impact of being seen as a baseball representative of the United States. Regression results are consistent with the conclusion that negative publicity devalues the cards of nonWhite players but not of White players. Positive publicity, however, increases the value of a player's card regardless of ethnicity. 相似文献