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191.
In a special paired sample case, Hotelling’s T2 test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given.  相似文献   
192.
Improved point and interval estimation of the smallest scale parameter of n independent populations following two-parameter exponential distributions are studied. The model is formulated in such a way that allows for treating the estimation of the smallest scale parameter as a problem of estimating an unrestricted scale parameter in the presence of a nuisance parameter. The classes of improved point and interval estimators are enriched with Stein-type, Brewster and Zidek-type, Maruyama-type and Strawderman-type improved estimators under both quadratic and entropy losses, whereas using as a criterion the coverage probability, with Stein-type, Brewster and Zidek-type, and Maruyama-type improved intervals. The sampling framework considered incorporates important life-testing schemes such as i.i.d. sampling, type-II censoring, progressive type-II censoring, adaptive progressive type-II censoring, and record values.  相似文献   
193.
地区收入、食品价格与恩格尔系数   总被引:2,自引:0,他引:2  
陈梦根 《统计研究》2019,36(6):28-41
本文以2016年我国31个省级地区截面数据为样本,构建扩展模型考察恩格尔系数与收入、食品价格之间的关系。研究发现,恩格尔系数与地区收入存在显著的负相关性,纳入食品价格后收入对恩格尔系数的影响变得更为显著,二者关系满足恩格尔定律。恩格尔系数和以地区食品价格平价代表的食品价格之间显著正相关,若再考虑其他因素,则食品价格对恩格尔系数的影响会稍有减弱。进一步将食品区分为生活必需型食品与非生活必需型食品,测算得到的基本恩格尔系数、高阶恩格尔系数与收入之间仍呈负相关关系,但与基本恩格尔系数相比,高阶恩格尔系数与收入之间的负相关性更弱。恩格尔系数受生活必需型食品价格的影响强于非生活必需型食品价格的影响,基本恩格尔系数主要受生活必需型食品价格的影响,而高阶恩格尔系数同时受到两类食品价格的影响。  相似文献   
194.
Assessment of analytical similarity of tier 1 quality attributes is based on a set of hypotheses that tests the mean difference of reference and test products against a margin adjusted for standard deviation of the reference product. Thus, proper assessment of the biosimilarity hypothesis requires statistical tests that account for the uncertainty associated with the estimations of the mean differences and the standard deviation of the reference product. Recently, a linear reformulation of the biosimilarity hypothesis has been proposed, which facilitates development and implementation of statistical tests. These statistical tests account for the uncertainty in the estimation process of all the unknown parameters. In this paper, we survey methods for constructing confidence intervals for testing the linearized reformulation of the biosimilarity hypothesis and also compare the performance of the methods. We discuss test procedures using confidence intervals to make possible comparison among recently developed methods as well as other previously developed methods that have not been applied for demonstrating analytical similarity. A computer simulation study was conducted to compare the performance of the methods based on the ability to maintain the test size and power, as well as computational complexity. We demonstrate the methods using two example applications. At the end, we make recommendations concerning the use of the methods.  相似文献   
195.
196.
Recent work has documented the need to engage with how men construct masculinities within postfeminist discourses in the workplace. Postfeminism has sparked debates concerning the changing ideals of masculinities, highlighting the tensions between traditional forms of patriarchy and ‘new’ ways of being a man (e.g., emotional, a ‘new father’, in crisis). Men have been depicted as being in search of a new identity, opposed to the ever‐growing confidence and empowerment of women. In mobilizing postfeminism as a discourse, this article illustrates how men working in an Italian pharmacological research centre (managed by men but dominated by women) assume subject positions that contradictorily fluctuate between tradition and fluid modernity, to reveal a masculinity which we identify with the ‘new industrial man’. The postfeminist masculinities exposed in the analysis mesh pro‐ and anti‐feminist ideas by appealing to un/heroic and romanticized subjectivities. The analysis also shows how un/heroic masculinities and men's appeal to biological differences to reinforce social ones and devalue the feminine obfuscate organizational gender inequalities. The article advances masculinity theory by offering a nuanced analysis of how masculinities and men are affected by paradoxical contemporary pressures for more egalitarian gender relations and a renewed emphasis on patriarchal traditions, which continue to support the gendering of the workplace.  相似文献   
197.
Sierra Leone experienced an 11-year civil war, brutalizing its people and destroying its communities. With the cessation of violence, international organizations helped to secure peace, deliver aid and supplies, and, after, assist with development projects. This grounded theory study, which aims to understand the role these organizations played from the viewpoint of community members in 2 communities, posits that community members’ regard of international organizations lessened as their efforts transitioned from securing the peace and relief efforts to aid for development. Highlighted are the successes and challenges of this work and a broad discussion of implications and recommendations.  相似文献   
198.
Payment by results is a relatively new way of giving development aid, where a recipient's performance against pre‐agreed measures determines the amount of aid they receive. Advocates for the mechanism argue it provides donors with both a ready justification for maintaining aid budgets and better results through innovation and autonomy. It has proved popular, with most bilateral aid donors having at least experimented with the mechanism and the variety of measures stretching from individual health workers being paid for each procedure, to national governments being paid for students' test scores. However, there has not been a robust assessment of whether Payment By Results (PbR) achieves its aims for greater effectiveness. I synthesize the evidence from eight projects fully or partially funded by DFID, the recognized world leader on PbR. This represents the best evidence currently available, and is critically analysed using the leading theoretical framework that breaks each agreement into its constituent parts. I find no evidence that PbR leads to fundamentally more innovation or autonomy, with the overall range of success and failure broadly similar to other aid projects. This may partly be due to the current use of Payment by Results, with no readily identifiable examples of projects that truly meet the idealized PbR designs. Advocates of PbR may thus conclude the idea is yet to be tested. I argue PbR does not deal with the fundamental constraints that donors face, and so it is unsurprising that PbR is subject to the normal pressures that affect all aid spending.  相似文献   
199.
As numbers of families with same-sex parents increase in the United States, children are more likely to encounter diverse family structures. Given that young children can demonstrate in-group bias, prejudicial attitudes, and social exclusion, it is important to understand how children perceive their peers in diverse families. To our knowledge, no studies have assessed elementary-school-age children's attitudes about same-sex parent families. Here, 131 elementary school students (Mage = 7.79 years; 61 girls) viewed images of same-sex (female and male) and other-sex couples with a child and then were asked about their perceptions of these families, particularly the children. Results indicated participants' preferences toward children with other-sex versus same-sex parents. Developmental and practical implications about children's attitudes toward sexual minority parent families are discussed.  相似文献   
200.
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