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861.
Purpose: Many students who are lesbian, gay, bisexual, transgender, or queer (LGBTQ) face hostile school environments that can negatively impact their mental health and education. This study involved a photovoice project where high school students from a gay-straight alliance in the rural southeastern United States took photographs that depicted the issues LGBTQ students were facing and then exhibited their photographs and stories to individuals from the school system and local community to promote awareness, dialogue, and action. Methods: Twenty adults who attended the photovoice exhibit responded to an online survey about their experiences with the intervention. Results: Eighty-five percent of adults reported that the intervention made them think about issues they had not previously considered, including the struggles LGBTQ youths face, gender issues, and living in a rural community. Common emotions experienced at the intervention included feeling excited, concern for the youths, and proud of the youths. Furthermore, 81% of the adults indicated that they would take action or behave differently as a result of the intervention, including supporting and affirming LGBTQ students, using gender-neutral and -inclusive language, and confronting bias in themselves and others. Conclusions: Photovoice is a promising strategy for LGBTQ students to activate adult allies in their community.  相似文献   
862.
The effect of a single variable data point, x, on the usual test statistics for traditional hypothesis tests for means is analyzed. It is shown that an outlier may have a profound and unexpected effect on the test statistic. Although it might appear that an outlier would tend to lend support to the alternate hypothesis, it may in fact detract from the significance of the test. In one-population tests and analysis of variance (ANOVA), the value of x that maximizes the significance of the test statistic is given. This value does not have to be unusually large or small. In fact, it often falls within the range of the other sample points. In the general one-population case, the limiting value for the test statistic is shown to be +1. In the case involving more than one population, it is shown that the limiting value of the test statistic is a function only of the number of members in the samples and not their relative values. Special cases are identified in which the test statistic is shown to have unique characteristics depending on the characteristics of the data.  相似文献   
863.
ABSTRACT

The purposes of this paper are to abstract from a number of articles variance component estimation procedures which can be used for completely random balanced incomplete block designs, to develop an iterated least squares (ITLS) computing algorithm for calculating maximum likelihood estimates, and to compare these procedures by use of simulated experiments. Based on the simulated experiments, the estimated mean square errors of the ITLS estimates are generally less than*those for previously proposed analysis of variance and symmetric sums estimators.  相似文献   
864.
865.
This paper discusses the literature on the established determinants of productivity in the retail sector. It also draws attention to some neglected strands of research which provide useful insights into strategies that could allow productivity enhancements in this area of the economy. To date, very few attempts have been made to integrate different specialisms in order to explain what drives productivity in retail. Here this paper rectifies this omission by putting together studies from economics, geography, knowledge management and employment studies. It is the authors’ view that quantitative studies of retail productivity should focus on total factor productivity in retailing as the result of competition/composition effects, planning regulations, information and communications technology, the multinational operation element and workforce skills. Further, the fact that retail firms possess advantages that are transferable between locations suggests that investment in strategies enhancing the transfer of explicit and tacit knowledge between and within businesses are crucial to achieve productivity gains.  相似文献   
866.
Stereology typically concerns estimation of properties of a geometric structure from plane section information. This paperprovides a brief review of some statistical aspects of this rapidly developing field, with some reference to applications in the earth sciences. After an introductory discussion of the scope of stereology, section 2 briefly mentions results applicable when no assumptions can be made about the stochastic nature of the sampled matrix, statistical considerations then arising solelyfrom the ‘randomness’ of the plane section. The next two sections postulate embedded particles of specific shapes, the particular case of spheres being discussed in some detail.

References are made to results for ‘thin slices’ and other prob-ing mechanisms. Randomly located convex particles, of otherwise arbitrary shape, are discussed in section 5 and the review concludes with a specific application of stereological ideas to some data on neolithic mining.  相似文献   
867.
Editorial     
Drawing on texts written by young people aged 14–17 years in a school context in response to an invitation to write a page describing themselves and their vision of Ireland and to use the reverse side creatively for drawings, poems or songs, this article illustrates the methodological difficulties of exploring globalization and individualization in such texts. The indicators of globalization were global entertainment and consumer culture, global technology, references to international travel, and global concerns. The indicators of individualization were the absence of references to structural location, or the presence of references to choices, hopes or plans and related images. There were insurmountable methodological difficulties in differentiating between individualization in these terms and stereotypical ways of ‘doing boy/girl’. Hence, the typology that was created focussed on the global content of the main texts and back pages and their gendered content.  相似文献   
868.
In many problems of risk analysis, failure is equivalent to the event of a random risk factor exceeding a given threshold. Failure probabilities can be controlled if a decisionmaker is able to set the threshold at an appropriate level. This abstract situation applies, for example, to environmental risks with infrastructure controls; to supply chain risks with inventory controls; and to insurance solvency risks with capital controls. However, uncertainty around the distribution of the risk factor implies that parameter error will be present and the measures taken to control failure probabilities may not be effective. We show that parameter uncertainty increases the probability (understood as expected frequency) of failures. For a large class of loss distributions, arising from increasing transformations of location‐scale families (including the log‐normal, Weibull, and Pareto distributions), the article shows that failure probabilities can be exactly calculated, as they are independent of the true (but unknown) parameters. Hence it is possible to obtain an explicit measure of the effect of parameter uncertainty on failure probability. Failure probability can be controlled in two different ways: (1) by reducing the nominal required failure probability, depending on the size of the available data set, and (2) by modifying of the distribution itself that is used to calculate the risk control. Approach (1) corresponds to a frequentist/regulatory view of probability, while approach (2) is consistent with a Bayesian/personalistic view. We furthermore show that the two approaches are consistent in achieving the required failure probability. Finally, we briefly discuss the effects of data pooling and its systemic risk implications.  相似文献   
869.
Improved methodology was used to re-examine the weak correspondence between problem and pathological gamblers identified in population surveys and subsequent classification of these individuals in clinical interviews. The SOGS-R, the CPGI, the NODS and the Problem and Pathological Gambling Measure (PPGM), as well as questions about gambling participation and expenditures, were administered to a total of 7272 adults. Two clinicians then assessed each person's status, based on comprehensive written profiles derived from these questionnaire responses. Instrument classification was then compared to clinical classification. All four instruments correctly classified most non-problem gamblers (i.e. had good to excellent sensitivity, specificity and negative predictive power). However, the PPGM was the only instrument with good classification of problem gamblers (i.e. excellent sensitivity and positive predictive power). The CPGI and SOGS-R had weak positive predictive power and the NODS had only adequate sensitivity and positive predictive power. Improvement in the classification accuracy of the CPGI occurred when a 5+ cut-off was used and when a 4+ cut-off was used with the SOGS. In general, the classification accuracy of the NODS, SOGS and CPGI is better than prior research suggested but overall accuracy is still modest. With adjusted cut-offs, all three instruments are reasonably congruent with clinical ratings.  相似文献   
870.
Austin Turk theorizes that places in stratification hierarchies affect police–citizen encounters by reinforcing or reversing the positional authority of police officers. To this point, however, there have been only three direct tests of the stratification portions of Turk's theory. Two examined overt conflict and all represented Turk's concepts using aggregated measures. The results are mixed. The present research adds a fourth test to the stratification and policing literatures by examining the effects of aggregated as well as disaggregated measures of stratification reinforcers and reversals on traffic ticket decisions by Boston police officers during April and May of 2001. Net of important control measures, there is no support for Turk's theory using the aggregated stratification measures employed in previous research. However, support for Turk's theory is clearly visible when viewed through the lens of some of the disaggregated stratification measures advanced for the first time in present research. We conclude that more research is needed to determine whether stratification reinforcers and reversals are among the factors affecting people in police blue and the people they police, with a sustained focus on both aggregated and disaggregated measures.  相似文献   
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