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481.
Legal interventions have succeeded in creating new opportunities for female athletes, but some argue that this is at the expense of opportunities for male athletes. In this review, we examine the consequences of a particular legal intervention in sport, the US education law Title IX, for female athletes, male athletes, and the construction of gender. Research indicates that sport participation is linked to important attainment outcomes, such as completing education and receiving higher salaries, for both male and female athletes. In addition, playing sports has several protective effects for women’s and girls’ mental and physical health. While positive effects for male athletes are important, courts’ interpretations of Title IX do not require the elimination of men’s opportunities but also do not protect those opportunities in current enforcement. Legal interventions that assure female sports participation also challenge the ways sport is used to create and reproduce definitions of masculinity, exposing dangerous emphases on toughness, aggressiveness, and heterosexual conquest that are damaging to both female and male athletes. 相似文献
482.
Erectile dysfunction frequently occurs with diabetes mellitus. A survey of diabetic men was conducted by anonymous questionnaire to investigate the associations of erectile dysfunction with various predictive factors. A total of 112 diabetic males without an obvious history of erectile dysfunction were available for analyses. The mean age and duration of diabetes were 53.7?±?12.2 years and 10.2?±?8.6 years (mean?±?standard deviation), respectively. The questionnaire included questions on the presence or absence of smoking, hypertension, libido and subjective symptoms of diabetic neuropathy that may be associated with erectile dysfunction. Analysis of the answers to the questionnaire revealed that 40% of the patients complained of erectile dysfunction (erection ‘always insufficient’). Erectile dysfunction was significantly correlated with age (p?=?0.005), but not with duration of diabetes (p?=?0.25), adjusted for age. Erectile dysfunction was also associated with sensory neuropathy and reduced libido, independently of age. The logistic regression analysis revealed that erectile dysfunction was positively associated with reduced libido and age. The odds ratio of erectile dysfunction for reduced compared to unreduced libido was 18.21, suggesting that psychogenic factors have a marked influence on erectile dysfunction. It is concluded that the presence of erectile dysfunction should be considered when symptoms related to diabetic neuropathy are observed; psychological approaches, such as sexual counseling, could be applied for the treatment of erectile dysfunction. 相似文献
483.
We demonstrate the existence and uniqueness of optimal observation schedules for discrete observation of the simple death process. Optimality is framed in the sense of observing the process at times that maximise the Fisher information for the death rate. We examine the relationship of our designs with those obtained by other authors for the simple birth process. A number of interesting properties are uncovered. Practical considerations in the application of these designs in an experimental setting are investigated, and we examine the performance of some approximately optimal designs that are usually simpler to implement. We will show that our optimal designs are highly robust to mis-specification of the death rate. 相似文献
484.
K.R. Clarke 《统计学通讯:理论与方法》2013,42(15):1459-1478
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
485.
Surviving the aftermaths of the Asian Financial Crisis and SARS in 2003, Hong Kong’s economy has re-gained its momentum and
its economic growth has been quite remarkable too in recent few years. Nevertheless, as reflected by the Social Development
Index (SDI), economic growth in Hong Kong does not seem to have benefited the people of the city at large as we see social
qualities such as cohesion, security, equity, and empowerment are gradually eroded. This paper aims to summarize the current
state of social development in Hong Kong based on the SDI-2008 and identify the major social, political and economic challenges
that are confronted by Hong Kong. Based on the findings, a range of policy options proposed for promoting a more balanced
approach to social and economic development are discussed. The article illustrates the utility of social indicators research
such as the SDI in assessing quality of life and assisting related social planning initiatives in Asian communities such as
Hong Kong. 相似文献
486.
Foulkes AS Azzoni L Li X Johnson MA Smith C Mounzer K Montaner LJ 《The annals of applied statistics》2010,4(3):1476-1497
Assessment of circulating CD4 count change over time in HIV-infected subjects on antiretroviral therapy (ART) is a central component of disease monitoring. The increasing number of HIV-infected subjects starting therapy and the limited capacity to support CD4 count testing within resource-limited settings have fueled interest in identifying correlates of CD4 count change such as total lymphocyte count, among others. The application of modeling techniques will be essential to this endeavor due to the typically non-linear CD4 trajectory over time and the multiple input variables necessary for capturing CD4 variability. We propose a prediction based classification approach that involves first stage modeling and subsequent classification based on clinically meaningful thresholds. This approach draws on existing analytical methods described in the receiver operating characteristic curve literature while presenting an extension for handling a continuous outcome. Application of this method to an independent test sample results in greater than 98% positive predictive value for CD4 count change. The prediction algorithm is derived based on a cohort of n = 270 HIV-1 infected individuals from the Royal Free Hospital, London who were followed for up to three years from initiation of ART. A test sample comprised of n = 72 individuals from Philadelphia and followed for a similar length of time is used for validation. Results suggest that this approach may be a useful tool for prioritizing limited laboratory resources for CD4 testing after subjects start antiretroviral therapy. 相似文献
487.
488.
Stephen K. McNees 《商业与经济统计学杂志》2013,31(1):126-127
This article develops a new identification procedure to estimate the contemporaneous relation between monetary policy and the stock market within a vector autoregression (VAR) framework. The approach combines high-frequency data from the futures market with the VAR methodology to circumvent exclusion restrictions and achieve identification. Our analysis casts doubt on VAR models imposing a recursive structure between innovations in policy rates and stock returns. We find that a tightening in policy rates has a negative impact on stock prices and that the Federal Reserve (Fed) has responded significantly to movements in the stock market. Estimates are robust to various model specifications. 相似文献
489.
H. K. Hsieh 《统计学通讯:理论与方法》2013,42(11):1335-1355
A class of linear rank tests is suggested for testing a shift in scale at an unknown time point in a sequence of independent observations. The tests,based on inverse normal scores and on ordered exponential scores,are shown to be asymptotically as efficient as their distribution-oriented competitors. Critical values and powers for these two rank tests are also discussed. 相似文献
490.
The authors establish the joint distribution of the sum X and the maximum Y of IID exponential random variables. They derive exact formuli describing the random vector (X, Y), including its joint PDF, CDF, and other characteristics; marginal and conditional distributions; moments and related parameters; and stochastic representations leading to further properties of infinite divisibility and self-decomposability. The authors also discuss parameter estimation and include an example from climatology that illustrates the modeling potential of this new bivariate model. 相似文献