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301.
Juan Chen Gilbert C. Gee Michael S. Spencer Sheldon H. Danziger David T. Takeuchi 《Social science research》2009,38(4):858-869
We investigate the association between a subjective measure of social status and the reasons for immigration among Asian immigrants in the US. We use data from the National Latino and Asian American Study to test several hypotheses about this association. Our analyses show the positive effect on perceived social standing of migrating for better education, the negative effect of migrating to seek employment, and the negative impact of refugee status. Migrating for family reunification can be associated with various circumstances, which lead to differing outcomes. The results suggest that the notion that immigrants arrive in the US with limited resources and few skills and move slowly up the socioeconomic ladder must be reassessed in light of the complex social context and factors such as ethnicity, gender, divergent immigration paths, and a range of associated circumstances. 相似文献
302.
In response surface methodology, one is usually interested in estimating the optimal conditions based on a small number of experimental runs which are designed to optimally sample the experimental space. Typically, regression models are constructed from the experimental data and interrogated in order to provide a point estimate of the independent variable settings predicted to optimize the response. Unfortunately, these point estimates are rarely accompanied with uncertainty intervals. Though classical frequentist confidence intervals can be constructed for unconstrained quadratic models, higher order, constrained or nonlinear models are often encountered in practice. Existing techniques for constructing uncertainty estimates in such situations have not been implemented widely, due in part to the need to set adjustable parameters or because of limited or difficult applicability to constrained or nonlinear problems. To address these limitations a Bayesian method of determining credible intervals for response surface optima was developed. The approach shows good coverage probabilities on two test problems, is straightforward to implement and is readily applicable to the kind of constrained and/or nonlinear problems that frequently appear in practice. 相似文献
303.
Julian P. T. Higgins Simon G. Thompson David J. Spiegelhalter 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2009,172(1):137-159
Summary. Meta-analysis in the presence of unexplained heterogeneity is frequently undertaken by using a random-effects model, in which the effects underlying different studies are assumed to be drawn from a normal distribution. Here we discuss the justification and interpretation of such models, by addressing in turn the aims of estimation, prediction and hypothesis testing. A particular issue that we consider is the distinction between inference on the mean of the random-effects distribution and inference on the whole distribution. We suggest that random-effects meta-analyses as currently conducted often fail to provide the key results, and we investigate the extent to which distribution-free, classical and Bayesian approaches can provide satisfactory methods. We conclude that the Bayesian approach has the advantage of naturally allowing for full uncertainty, especially for prediction. However, it is not without problems, including computational intensity and sensitivity to a priori judgements. We propose a simple prediction interval for classical meta-analysis and offer extensions to standard practice of Bayesian meta-analysis, making use of an example of studies of 'set shifting' ability in people with eating disorders. 相似文献
304.
In this note we provide a counterexample which resolves conjectures about Hadamard matrices made in this journal. Beder [1998. Conjectures about Hadamard matrices. Journal of Statistical Planning and Inference 72, 7–14] conjectured that if H is a maximal m×n row-Hadamard matrix then m is a multiple of 4; and that if n is a power of 2 then every row-Hadamard matrix can be extended to a Hadamard matrix. Using binary integer programming we obtain a maximal 13×32 row-Hadamard matrix, which disproves both conjectures. Additionally for n being a multiple of 4 up to 64, we tabulate values of m for which we have found a maximal row-Hadamard matrix. Based on the tabulated results we conjecture that a m×n row-Hadamard matrix with m?n-7 can be extended to a Hadamard matrix. 相似文献
305.
David E. Tyler Frank Critchley Lutz Dümbgen Hannu Oja 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2009,71(3):549-592
Summary. A general method for exploring multivariate data by comparing different estimates of multivariate scatter is presented. The method is based on the eigenvalue–eigenvector decomposition of one scatter matrix relative to another. In particular, it is shown that the eigenvectors can be used to generate an affine invariant co-ordinate system for the multivariate data. Consequently, we view this method as a method for invariant co-ordinate selection . By plotting the data with respect to this new invariant co-ordinate system, various data structures can be revealed. For example, under certain independent components models, it is shown that the invariant co- ordinates correspond to the independent components. Another example pertains to mixtures of elliptical distributions. In this case, it is shown that a subset of the invariant co-ordinates corresponds to Fisher's linear discriminant subspace, even though the class identifications of the data points are unknown. Some illustrative examples are given. 相似文献
306.
Happily Religious: The Surprising Sources of Happiness Among Lesbian,Gay, Bisexual,and Transgender Adults 下载免费PDF全文
This article analyzes the impact of religion on reported levels of subjective well‐being (general happiness) among lesbian, gay, bisexual, and transgender (LGBT) adults. Although previous studies find religious affiliation to be a significant predictor of subjective well‐being among the general population in the United States, limited quantitative research investigates general happiness among sexual and gender minorities. This study augments the existing literature by using a national survey of LGBT adults conducted by the Pew Research Center in 2013. The results show that religious affiliation is a significant predictor of LGBT individuals’ happiness. LGBT individuals who identify as Catholic, agnostic or atheist, or with no particular religious affiliation report lower levels of happiness compared to mainline Protestants. Surprisingly, no significant differences are found between mainline Protestants (whose church doctrine often accepts same‐sex relations) and evangelical Protestants (whose church doctrine often condemns same‐sex relations). In addition, income is the only control variable that affects general happiness. Our analysis reveals interesting differences in the determinants of subjective well‐being between the LGBT and general population. 相似文献
307.
308.
309.
Driving outcomes: learning to drive,resilience and young people living in residential care 下载免费PDF全文
David Berridge 《Child & Family Social Work》2017,22(1):77-85
There are continuing concerns about the experiences offered to older adolescents being looked after (‘in care’) in the UK and, especially, to care leavers. Questions are asked about the limitations of State care compared with normal family life. This paper reports on an initiative to provide driving lessons to a group of six young men living in residential homes in one city. It links with resilience theory – how individuals can have relatively good outcomes despite early adversity. A qualitative study was undertaken to explore the effects of the initiative, including individual interviews with young men, heads of homes in which they lived and children's services managers. The overall results indicated that the initiative was very worthwhile. The lessons were a significant part of young people's lives. Possible effects on young people were divided into personal, instrumental and social. Benefits were reported from all parties concerning young people's self‐esteem and self‐confidence, as well as in forging close relationships with supportive adults. Driving would not be seen as a panacea for complex personal histories and structural problems, yet this small experiment suggests that driving lessons could be of disproportionate benefit and there is a moral obligation to provide them in any case. 相似文献
310.
Sowmya Rajan S. Philip Morgan Kathleen Mullan Harris David Guilkey Sarah R. Hayford Karen Benjamin Guzzo 《Population research and policy review》2017,36(6):903-928
Having an unintended birth is strongly associated with the likelihood of having later unintended births. We use detailed longitudinal data from the Add Health Study (N = 8300) to investigate whether a host of measured sociodemographic, personality, and psychosocial characteristics select women into this “trajectory” of unintended childbearing. While some measured characteristics and aspects of the unfolding life course are related to unintended childbearing, explicitly modeling these effects does not greatly attenuate the association of an unintended birth with a subsequent one. Next, we statistically control for unmeasured time-invariant covariates that affect all birth intervals, and again find that the association of an unintended birth with subsequent ones remains strong. This persistent, strong association may be the direct result of experiencing an earlier unintended birth. We propose several mechanisms that might explain this strong association. 相似文献