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Latina female (n= 97) and Latino male (n= 69) college students (M age = 21.4 years) completed self‐report surveys regarding family of origin experiences, including sexual communication with parents while growing up. Latino parents of this comparatively highly educated sample tended to use direct rather than indirect strategies for communicating about sexuality with their children. Young women reported higher levels of sexual communication with mothers while growing up than did young men, and respondents reported less communication with fathers than mothers. Among young women, sexual communication with mother was positively associated with non‐Mexican origin and negatively associated with having older brothers living at home. In contrast, maternal education was positively associated with mother‐son communication about sex. Paternal education and the absence of older brothers positively predicted communication with both sons and daughters. The analyses provide novel information regarding sexual communication in Latino families and suggest directions for future research. 相似文献
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Craig H. Mallinckrodt John G. Watkin Geert Molenberghs Raymond J. Carroll 《Pharmaceutical statistics》2004,3(3):161-169
Missing data, and the bias they can cause, are an almost ever‐present concern in clinical trials. The last observation carried forward (LOCF) approach has been frequently utilized to handle missing data in clinical trials, and is often specified in conjunction with analysis of variance (LOCF ANOVA) for the primary analysis. Considerable advances in statistical methodology, and in our ability to implement these methods, have been made in recent years. Likelihood‐based, mixed‐effects model approaches implemented under the missing at random (MAR) framework are now easy to implement, and are commonly used to analyse clinical trial data. Furthermore, such approaches are more robust to the biases from missing data, and provide better control of Type I and Type II errors than LOCF ANOVA. Empirical research and analytic proof have demonstrated that the behaviour of LOCF is uncertain, and in many situations it has not been conservative. Using LOCF as a composite measure of safety, tolerability and efficacy can lead to erroneous conclusions regarding the effectiveness of a drug. This approach also violates the fundamental basis of statistics as it involves testing an outcome that is not a physical parameter of the population, but rather a quantity that can be influenced by investigator behaviour, trial design, etc. Practice should shift away from using LOCF ANOVA as the primary analysis and focus on likelihood‐based, mixed‐effects model approaches developed under the MAR framework, with missing not at random methods used to assess robustness of the primary analysis. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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李社教 《武汉理工大学学报(社会科学版)》2002,15(4):332-336
实践美学从历史唯物主义出发 ,指出了美感和美是社会历史实践的产物。它是一种凸现了人、人的活动、人的自由活动的美学。在理论上 ,实践美学顺应历史的潮流 ,宣告了形而上学的终结 ,走出了古典主义的二元对立思维模式 ;在现实上 ,实践美学针对时代的虚无 ,高扬人的旗帜 ,为美学研究开辟了一片新的天地。 相似文献
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Longitudinal data often contain missing observations, and it is in general difficult to justify particular missing data mechanisms, whether random or not, that may be hard to distinguish. The authors describe a likelihood‐based approach to estimating both the mean response and association parameters for longitudinal binary data with drop‐outs. They specify marginal and dependence structures as regression models which link the responses to the covariates. They illustrate their approach using a data set from the Waterloo Smoking Prevention Project They also report the results of simulation studies carried out to assess the performance of their technique under various circumstances. 相似文献
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朱彝尊“醇雅说”之探讨 总被引:1,自引:0,他引:1
李哲理 《东北大学学报(社会科学版)》2003,5(6):455-460
指出浙西派创始人朱彝尊以其独特的"醇雅说"而在清代众多文学流派中独树一帜,其崇雅正、斥淫哇、抑豪放、偏清空的创作理念对当时及后世都产生了广泛的影响。结合朱氏生活的时代背景及其创作的大量的诗词作品,从多个角度探讨了朱氏作品的旨趣与风格,以期最终描绘出"醇雅说"的内涵及其在指导诗词创作中重要的理论价值。 相似文献
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言语生成 (speechproduction)和言语理解 (speechunderstanding)是语言交际中十分复杂的心理认知过程 ,也是心理语言学研究中的一个重要内容。本文拟对有关言语生成和理解的几种心理模型予以讨论 ,探讨言语生成及理解的过程和实质。 相似文献
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Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern. 相似文献
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在全面推行素质教育的形势下,教育者自身的心理素质与心育能力显得日益重要。针对目前从教育心理学角度发现的一些教师容易出现的心理缺失状态,学校应采取相应的措施提高教学视野中教师的心育能力,以更好地发挥教与学的双主体作用。 相似文献