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921.
Eight different variable selection techniques for model-based and non-model-based clustering are evaluated across a wide range of cluster structures. It is shown that several methods have difficulties when non-informative variables (i.e., random noise) are included in the model. Furthermore, the distribution of the random noise greatly impacts the performance of nearly all of the variable selection procedures. Overall, a variable selection technique based on a variance-to-range weighting procedure coupled with the largest decreases in within-cluster sums of squares error performed the best. On the other hand, variable selection methods used in conjunction with finite mixture models performed the worst.  相似文献   
922.
在医疗过程中,无法取得患者的同意时,通常由他人代其做出同意。但是,代为同意人在代为做出同意时,必须以患者本人的最佳利益为原则。在判断患者的最佳利益时,可以借鉴英国《心智能力法2005》的规定,通过对诸因素的评估,来综合决定何谓患者的最佳利益。我国在制订和修改代为同意的相关规定时,应该考虑如何借鉴英国的规定,制订符合我国国情的代为同意制度。  相似文献   
923.
为了了解剖宫产患者产后抑郁的发生情况,对剖宫产患者进行抑郁状况的调查,并对其影响因素进行分析,对抑郁组与非抑郁组的一般情况构成比比较,并采用抑郁自评量表(SDS)、应付方式评定量表(YFFS)、社会支持问卷(ISSI)进行测评。结果显示,应付方式评定量表中的主观支持(P〈0.05),社会支持问卷中退避倾向性进入回归方程,提示应付方式及社会支持是影响剖宫产患者产后抑郁的重要因素。  相似文献   
924.
医疗纠纷泛化原因多视角分析   总被引:2,自引:1,他引:1  
随着社会的发展,医疗纠纷日趋增多,成为各卫生部门的最大难题,是继医疗改革之后的又一备受社会各界关注的热门话题,医患关系成为社会最不和谐的声音。医患关系是在社会政治、经济、文化、法律等因素共同作用,围绕“治病”所形成的道德、诚信、契约、经济利益关系,通过分析现代医患关系的变化,探讨医疗纠纷增多的原因。  相似文献   
925.
福柯与《临床医学的诞生》   总被引:1,自引:0,他引:1  
《临床医学的诞生》是20世纪法国著名学者福柯的一部医学史研究专著,主要从空间、语言和死亡三个方面探讨了现代医学也就是临床医学诞生的可能性条件,兼具历史与批判的性质。它揭示了隐藏在医学话语背后的权力关系,反映了福柯瓦解传统、颠覆理性的新型历史观。  相似文献   
926.
A number of recent studies have questioned the conventional view regarding the existence of income-related inequalities in depression and have suggested that other factors have a more marked impact, most notably those socio-environmental effects linked to professional status and educational attainment. This paper seeks to measure and decompose the degree of socio-economic inequality in the factors underlying reported depression by drawing on data from Spain (Spanish National Health Survey, 2003), a country in which mental care coverage is somewhat limited, but where a marked social transformation has been apparent in recent decades. Contrary to recent evidence, our findings point towards the existence of significant income-related inequalities in the prevalence of reported (diagnosed) depression. However, the results from our decomposition analysis are more mixed. While a modest proportion of overall inequalities (6–13%) is accounted for by income alone, labour status, demographics and education appear to be more relevant. However, when controlling for potential endogeneity between income and depression by using instrumental variables (IV), income is found to account for more than 50% of overall inequality in reported depression.
Joan Costa-FontEmail:
  相似文献   
927.
初中生自我调节学习的类型及对学习的影响   总被引:4,自引:1,他引:3       下载免费PDF全文
自我调节学习是一种学习者主动激励自己并积极使用适当的学习策略的学习,研究利用潜在剖面分析法和辨别分析法对316名初中生自我调节学习的类型进行考察,探讨不同自我调节学习类型初中生的特点,分析自我调节学习类型对学习动机、焦虑、学习成绩的影响。结果表明:(1)初中生自我调节学习分成综合发展型、均衡调节型和策略滞后型3种。(2)综合发展型初中生的自我调节学习水平最高,策略滞后型初中生的自我调节学习水平尤其是学习策略水平最低,而均衡调节型初中生的自我调节学习水平处于综合发展型和策略滞后型之间。(3)自我调节学习类型对学习动机、焦虑、学习成绩有影响。  相似文献   
928.
TIM DE MEY 《Metaphilosophy》2006,37(2):222-239
Abstract: In part because “imagination” is a slippery notion, its exact role in the production of scientific knowledge remains unclear. There is, however, one often explicit and deliberate use of imagination by scientists that can be (and has been) studied intensively by epistemologists and historians of science: thought experiments. The main goal of this article is to document the varieties of thought experimentation, not so much in terms of the different sciences in which they occur but rather in terms of the different functions they fulfil. I argue that thought experimentation (and hence imagination) plays a role not only in theory choice but in singular causal analysis and scientific discovery as well. I pinpoint, moreover, some of the rules governing the use of thought experiments in theory choice and in singular causal analysis, that is, some of the criteria they should meet in order to fulfil those functions successfully.  相似文献   
929.
Electronic searches were conducted on PubMed and the American Psychological Association's database (PsycINFO) for articles that discussed the role of rabbis in relation to some aspect of healthcare. The two searches were conducted in each electronic database using the search-terms: (1) (rabbi OR rabbinical OR synagogue) OR (2) (Judaism OR Jewish) AND (clergy OR chaplain). Articles were classified by the year of their publication, professional discipline, type of journal (either religious or secular), and type of article: either research, or narrative and expositional. Rabbis were discussed most often in psychology, psychiatry, and behavior-related fields, and close to two-thirds of the articles dealt with mental health concerns. A statistically significant increase in articles across decades was found in the secular journals, r=.98, p≤.01, with over 70% of the articles about rabbis in the secular journals being published between 1980 and 1999. Many of the articles addressed collaboration between rabbis, psychiatrists, and other and mental health professionals and discussed previously identified themes related to professional collaboration and referral.  相似文献   
930.
Discretized multivariate normal structural models are often estimated using multistage estimation procedures. The asymptotic properties of parameter estimates, standard errors, and tests of structural restrictions on thresholds and polychoric correlations are well known. It was not clear how to assess the overall discrepancy between the contingency table and the model for these estimators. It is shown that the overall discrepancy can be decomposed into a distributional discrepancy and a structural discrepancy. A test of the overall model specification is proposed, as well as a test of the distributional specification (i.e., discretized multivariate normality). Also, the small sample performance of overall, distributional, and structural tests, as well as of parameter estimates and standard errors is investigated under conditions of correct model specification and also under mild structural and/or distributional misspecification. It is found that relatively small samples are needed for parameter estimates, standard errors, and structural tests. Larger samples are needed for the distributional and overall tests. Furthermore, parameter estimates, standard errors, and structural tests are surprisingly robust to distributional misspecification. This research was supported by the Department of Universities, Research and Information Society (DURSI) of the Catalan Government, and by grants BSO2000-0661 and BSO2003-08507 of the Spanish Ministry of Science and Technology.  相似文献   
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