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251.
This paper extensively investigates the theory of estimating the regression coefficient matrix in the normal GM.4KOVA model. We explicitly construct estimators which improve upon the maximum likelihood estimator under an invariant scalar loss function. These include the double shrinkage estimatois and those shrinking the maximum likelihood estimators directly. The underlying method is the decomposition of the problem into the conditional subproblems due to Kariya, Konno, and Strawderman(l996) and application of integration-by-parts technique to derive an unbiased estimate of the risk for certain class of invariant estimators.  相似文献   
252.
We examined the validity of three leadership approaches in an organization in India. We used a multi-theory and multi-method design to competitively test transformational leadership theory, the nurturant–task leadership model, and a local organization-specific leadership model. Transformation leadership theory is one of the most widely studied and accepted theories in Western countries and is viewed as a universalistic leadership approach. The nurturant–task leadership model was developed in India and viewed as a culture-specific leadership approach. We also developed a local leadership model, called RDO, a pseudonym for the organization, and viewed it as an organization-specific leadership approach, using a qualitative analysis of interview data. The overall results of our qualitative–quantitative work provide strong support for the RDO leadership model, some support for a nurturant–task leadership model, and minimal support for transformational leadership theory. These results suggest that research designs that include a multi-theory, multi-methods approach in a single culture have the potential to increase our understanding of leadership processes.  相似文献   
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254.
Abstract

Objectives: This exploratory study examined pre-event drinking, or pregaming, by US college students. Participants: 112 undergraduates from 10 Pennsylvania colleges participated. Method: A focus group, including a written questionnaire, was conducted at each institution. Results: Only 35.7% of the participants had not pregamed during the last 2 weeks. Pregamers consumed an average of 4.9 (SD = 3.1) drinks during their most recent session. Gender, class year, and other demographic variables did not predict pregaming. Heavier drinkers, and those stating that the average student pregamed 3+ times in the last 2 weeks, were more likely to report pregaming in the last 2 weeks. How much students drink when pregaming is influenced by how much they expect to drink later on. Conclusion: Pregaming presents a growing challenge for campus officials. Additional research is needed on the nature of the problem and which combination of prevention strategies might best address this behavior.  相似文献   
255.
Many of the procedures undertaken within healthcare require specialized forms of participation that may be unfamiliar, even disturbing, to patients or clients. The practitioner has to encourage and enable participation in the investigation in an appropriate fashion while preserving the structure and integrity of the procedure. In this article, we consider optometry and the deployment of a vision test, known as subject refraction, that provides data to help determine the characteristics of any corrective lens that may be required by clients. The procedure's ability to establish robust and reliable data relies upon the optometrist's ability to encourage the client to respond to a series of stimuli without consideration or reflection. That is, the client is required to produce an unwitting response—conduct that might be considered nonsymbolic rather than symbolic. In this article, we also consider the optometrist's talk and bodily comportment during subjective refraction and how it serves to shape and determine the quality of the client's response and participation, and in turn to produce reliable test results.  相似文献   
256.
The authors investigated the strategies that helped or hindered 10 immigrant women workers to do well with change that affected their work. A total of 182 incidents were extracted and grouped into 9 categories: personal beliefs/traits/ values, taking action, skills/education, personal challenges, self‐care, relationships/ support, government/community resources, work environment, and contextual challenges. Results support and extend contentions that both internal/personal and external factors are key successful adaptation to change for immigrant women. Implications for research and practice are discussed. Counseling recommendations are offered for individuals who are struggling with change.  相似文献   
257.
自1928年国民党统治开始,中国第一次进入了其现代意义上的国际合作关系时期,寻求国际伙伴关系首次成为中国内政与外交政策的主要目标.20世纪30年代和40年代早期的中德、中俄和中美关系各自具有鲜明的特性.中德关系建立在两国领导人互相信任和经验积累的基础之上,某些意识形态上的类似是其得以发展的主要因素,但更重要的是互补的经济利益使国民党可以实现平等的合作.中苏关系和中美关系一开始就是为了增强双方对付共同敌人的力量而形成结盟的,之前都不具有恰当的合作机制,而意识形态是一个复杂的、不利于结盟的因素.在中苏关系中,结盟意味着从直接敌对状态转向谨慎的合作.而中美之间非国家层面上的合作既没有达到一个较高的水平,这些合作也不会自动强化双方的官方关系.当结盟机制仓促建立起来时,却缺乏坚实的结构基础.  相似文献   
258.
Environmental education organizations can do more to either institute evaluation or improve the quality of their evaluation. In an effort to help evaluators bridge the gap between the potential for high quality evaluation systems to improve environmental education, and the low level of evaluation in actual practice, we reviewed recent environmental education literature to reveal the challenges and opportunities for evaluating environmental education programs. The literature review identified strategies for confronting the challenges in environmental education evaluation, as well as notable opportunities for increasing the quality of evaluation in environmental education.  相似文献   
259.
In 1992, a mental‐models‐based survey in Pittsburgh, Pennsylvania, revealed that educated laypeople often conflated global climate change and stratospheric ozone depletion, and appeared relatively unaware of the role of anthropogenic carbon dioxide emissions in global warming. This study compares those survey results with 2009 data from a sample of similarly well‐educated laypeople responding to the same survey instrument. Not surprisingly, following a decade of explosive attention to climate change in politics and in the mainstream media, survey respondents in 2009 showed higher awareness and comprehension of some climate change causes. Most notably, unlike those in 1992, 2009 respondents rarely mentioned ozone depletion as a cause of global warming. They were also far more likely to correctly volunteer energy use as a major cause of climate change; many in 2009 also cited natural processes and historical climatic cycles as key causes. When asked how to address the problem of climate change, while respondents in 1992 were unable to differentiate between general “good environmental practices” and actions specific to addressing climate change, respondents in 2009 have begun to appreciate the differences. Despite this, many individuals in 2009 still had incorrect beliefs about climate change, and still did not appear to fully appreciate key facts such as that global warming is primarily due to increased concentrations of carbon dioxide in the atmosphere, and the single most important source of this carbon dioxide is the combustion of fossil fuels.  相似文献   
260.
The quadratic discriminant function is commonly used for the two group classification problem when the covariance matrices in the two populations are substantially unequal. This procedure is optimal when both populations are multivariate normal with known means and covariance matrices. This study examined the robustness of the QDF to non-normality. Sampling experiments were conducted to estimate expected actual error rates for the QDF when sampling from a variety of non-normal distributions. Results indicated that the QDF was robust to non-normality except when the distributions were highly skewed, in which case relatively large deviations from optimal were observed. In all cases studied the average probabilities of misclassification were relatively stable while the individual population error rates exhibited considerable variability.  相似文献   
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