The impact of mortality development on the number of centenarians in England and wales

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.     

The Slaughtered and the Survivors: Collaboration Between Social Economy Organizations as a Key to Success in Times of Financial Crisis

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.     

Improved bridge constructs for stochastic differential equations

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.     

薪酬参照体的效应研究:基于多表征的路径模型与相对重要性

参照体选择在分配公平、薪酬满意研究中扮演重要角色,而以往研究多是关注焦点对象与参照体在薪酬上的数量差异。本文认为,参照体"数量差异"并不能完整表征参照体的效应,为此提出了"信息知晓度"、"判断关联性"、"比较频率"、"数量差异"等四类表征,在理论基础上构造路径模型与研究假设。实证研究表明,信息知晓度、判断关联性正向影响特定参照体的比较频率;数量差异正向影响分配公平、薪酬水平满意,比较频率负向影响分配公平、薪酬水平满意。通过三种研究路径的比较研究证实,自我生活成本等七类参照体相对重要。未来亟需就参照体选择的相关机制在纵贯上、在不同的组织情境下及考虑个体差异等方面予以深入考察。     

Estimating large-scale general linear and seemingly unrelated regressions models after deleting observations

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.     

Racial/Ethnic Disparities in Mental Health Service Use for Older Foster Youth and Foster Care Alumni

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.     

Are Daughters Like Mothers: Evidence on Intergenerational Educational Mobility Among Young Females in India

Taking data from the ‘India Youth Survey: Situation and Needs’ the paper examines intergenerational educational mobility for young females (vis-à-vis their mothers) in India. The paper uses transition/mobility matrices and mobility measures widely used in the literature on intergenerational mobility for the examination. The overall intergenerational educational mobility among the young females in India is about 0.69 (the upper limit being 1). The upwards component of the overall intergenerational educational mobility is 0.55 (that is, nearly four-fifth of the overall). Also, the intergenerational educational mobility is slightly higher in the ‘Scheduled Castes and Tribes (SC/ST)’ compared to the ‘Other Backward Castes (OBC)’ as well as ‘Others’ castes. But the upward mobility is substantially higher in the ‘Others’ caste group compared to SC/STs. The upward mobility among the OBCs is higher than that of SC/STs but lower than that of the ‘Others’ category. Also, the overall mobility as well as upward mobility is higher in urban areas. Moreover, there are large inter-state variations with the economically and demographically poorer states having substantially lower overall as well as upward mobility than the economically and demographically advanced states.