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81.
This article considers the analysis of complex monitored health data, where often one or several signals are reflecting the current health status that can be represented by a finite number of states, in addition to a set of covariates. In particular, we consider a novel application of a non-parametric state intensity regression method in order to study time-dependent effects of covariates on the state transition intensities. The method can handle baseline, time varying as well as dynamic covariates. Because of the non-parametric nature, the method can handle different data types and challenges under minimal assumptions. If the signal that is reflecting the current health status is of continuous nature, we propose the application of a weighted median and a hysteresis filter as data pre-processing steps in order to facilitate robust analysis. In intensity regression, covariates can be aggregated by a suitable functional form over a time history window. We propose to study the estimated cumulative regression parameters for different choices of the time history window in order to investigate short- and long-term effects of the given covariates. The proposed framework is discussed and applied to resuscitation data of newborns collected in Tanzania.  相似文献   
82.
In this paper, we consider the problem of making statistical inference for a truncated normal distribution under progressive type I interval censoring. We obtain maximum likelihood estimators of unknown parameters using the expectation-maximization algorithm and in sequel, we also compute corresponding midpoint estimates of parameters. Estimation based on the probability plot method is also considered. Asymptotic confidence intervals of unknown parameters are constructed based on the observed Fisher information matrix. We obtain Bayes estimators of parameters with respect to informative and non-informative prior distributions under squared error and linex loss functions. We compute these estimates using the importance sampling procedure. The highest posterior density intervals of unknown parameters are constructed as well. We present a Monte Carlo simulation study to compare the performance of proposed point and interval estimators. Analysis of a real data set is also performed for illustration purposes. Finally, inspection times and optimal censoring plans based on the expected Fisher information matrix are discussed.  相似文献   
83.
Some neo-Malthusians regard fertility as being kept in check by scarcities and constraints and, conversely, as being raised by economic prosperity. Since out-migration to developed countries and the receipt of food aid from developed countries relax the constraints imposed by a country’s carrying capacity, both will have a positive effect on fertility rates in developing countries. Moreover, better economic prospects will also raise fertility, all other things equal. This article provides an empirical test of these hypotheses derived from a neo-Malthusian theory of fertility change. The results fail to confirm the theory and often contradict it.
Eric NeumayerEmail: Fax: +44-207-9557412
  相似文献   
84.
基于201个城市的相关数据,利用动态面板模型和空间杜宾模型,实证分析了内循环、外循环和双循环对产业转移的影响。研究结果表明:前期产业转移在一定程度上会影响后期产业转移,前一期当地产业比例较大,其后产业转移受到的促进作用也较大;内循环、外循环和双循环均对产业转移起到显著的正向促进作用,东部城市受到的促进作用略高于中西部城市;要素流动在产业转移中发挥着重要作用,劳动力要素流动、技术要素流动和资本要素流动不仅受到内、外循环和双循环的促进作用,同时对产业转移也起到一定的促进作用;产业转移具有空间相关性,产业在空间上倾向于向产业转入较高的城区转移。为此,我国在政策上应进一步加快推动内循环,促进外循环,关注要素流动在产业转移中的重要作用,合理分配要素资源。  相似文献   
85.
An important source of neighborhood change occurs when there is a turnover in the housing unit due to residential mobility and the new residents differ from the prior residents based on socio-demographic characteristics (what we term social distance). Nonetheless, research has typically not asked which characteristics explain transitions with higher social distance based on a number of demographic dimensions. We explore this question using American Housing Survey data from 1985 to 2007, and focus on instances in which the prior household moved out and is replaced by a new household. We focus on four key characteristics for explaining this social distance: the type of housing unit, the age of the housing unit, the length of residence of the exiting household, and the crime and social disorder in the neighborhood. We find that transitions in the oldest housing units and for the longest tenured residents result in the greatest amount of social distance between new and prior residents, implying that these transitions are particularly important for fostering neighborhood socio-demographic change. The results imply micro-mechanisms at the household level that might help explain net change at the neighborhood level.  相似文献   
86.
Youth aging out of foster care are at high risk for homelessness. This research explains how and why homelessness occurs among youth with serious mental health struggles after aging out of residential and transitional living programmes. Using a longitudinal constructivist grounded theory design, we analyse 20 in‐depth interviews exploring youth's transition experiences and perceptions of transition success within 4 months of emancipation and at 6 and 12 months postemancipation. Monthly 15‐min check‐ins prevented attrition. A three‐phase transition process was observed driven by participant desires and actions to cultivate psychological home through establishing physical home alone away from social networks. Pre‐emancipation, the promise of home was privacy and opportunity for self‐redefinition. Shortly after emancipation, home became a physical and social space to be, a valuable resource to share and a demonstration of personal transition success. However, later in the year postemancipation, maintaining physical home proves nearly impossible given the risk context. Findings speak to how and why youth aging out appear overly self‐reliant upon emancipation. Cultivating a psychological sense of home has practice implications for child welfare providers who aim to prepare youth to live independently postemancipation.  相似文献   
87.
In this article, the quality of data produced by national statistical institutes and by governmental institutions is considered. In particular, the problem of measurement error is analyzed and an integrated Bayesian network decision support system based on non-parametric Bayesian networks is proposed for its detection and correction. Non-parametric Bayesian networks are graphical models expressing dependence structure via bivariate copulas associated to the edges of the graph. The network structure and the misreport probability are estimated using a validation sample. The Bayesian network model is proposed to decide: (i) which records have to be corrected; (ii) the kind and amount of correction to be adopted. The proposed correction procedure is applied to the Banca d’Italia Survey on Household Income and Wealth and, specifically, the bond amounts are analyzed. Finally, the sensitivity of the conditional distribution of the true value random variable given the observed one to different evidence configurations is studied.  相似文献   
88.
In this paper, Abdelfatah and Mazloum's (2015) two-stage randomized response model is extended to unequal probability sampling and stratified unequal probability sampling, both with and without replacement. The extended models result in more efficient estimators than Lee et al.'s (2014) estimators of the proportion of the population having a sensitive attribute.  相似文献   
89.
Objective: The purpose of this study was to assess the current state of postsecondary educational settings’ outreach to military women who become students postservice. Participants: Data for the present cross-sectional study were obtained from the American College Health Association’s (ACHA) 2011–2014 National College Health Assessment II (NCHA). Methods: Demographic characteristics of the study sample were explored by calculating frequencies and percentages by military service status. Research questions were explored with Fisher’s exact test, maximum likelihood multiple logistic regression, as appropriate. Results: Women service member and veteran students received health information from their university/college less often than women students with no military experience on the following topics: alcohol and other drug use, depression and anxiety, sexual assault and relationship violence prevention, and stress reduction. Conclusions: The findings of this research identified clear gaps in service provision for women student veterans on college campuses and provided some possible models for intervention development.  相似文献   
90.
Studies on youth leaving care have emphasized their limited social support and their need for continuing support after emancipation. However, less is known about the nature of their existing social networks after emancipation and their roles during their transition to adulthood compared with their noncare‐leaving peers. With this in mind, 32 young adults aged 18 to 25 participated in semi‐structured interviews regarding their current support figures in order to learn whether they were congruent with their needs after emancipation. Thematic analysis revealed four main features of the two groups' social networks: (a) stability versus uncertainty as to the lasting presence of the supportive figure, (b) reliance on parents as main supportive figures versus relying on different supportive figures, (c) confidence versus uncertainty in the supportive figures' ability to help, and (d) holistic versus fragmented support of the young adults' needs. The discussion addresses the unique characteristics of care leavers in emerging adulthood and the implications of their social networks' features for their adjustment after emancipation. One of the study's recommendations is to proactively connect them to new supportive figures such as professionals or mentors by offering them mentoring programs cognizant of the instrumental and developmental tasks of emerging adulthood.  相似文献   
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