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141.
Factor analysis is regularly used for analyzing survey data. Missing data, data with outliers and consequently nonnormal data are very common for data obtained through questionnaires. Based on covariance matrix estimates for such nonstandard samples, a unified approach for factor analysis is developed. By generalizing the approach of maximum likelihood under constraints, statistical properties of the estimates for factor loadings and error variances are obtained. A rescaled Bartlett-corrected statistic is proposed for evaluating the number of factors. Equivariance and invariance of parameter estimates and their standard errors for canonical, varimax, and normalized varimax rotations are discussed. Numerical results illustrate the sensitivity of classical methods and advantages of the proposed procedures.This project was supported by a University of North Texas Faculty Research Grant, Grant #R49/CCR610528 for Disease Control and Prevention from the National Center for Injury Prevention and Control, and Grant DA01070 from the National Institute on Drug Abuse. The results do not necessarily represent the official view of the funding agencies. The authors are grateful to three reviewers for suggestions that improved the presentation of this paper.  相似文献   
142.
We introduce non-associative linear logic, which may be seen as the classical version of the non-associative Lambek calculus. We define its sequent calculus, its theory of proof-nets, for which we give a correctness criterion and a sequentialization theorem, and we show proof search in it is polynomial.  相似文献   
143.
Casadio  Claudia  Lambek  Joachim 《Studia Logica》2002,71(3):315-329
In this paper we consider the relations existing between four deductive systems that have been called categorial grammars and have relevant connections with linguistic investigations: the syntactic calculus, bilinear logic, compact bilinear logic and Curry's semantic calculus.  相似文献   
144.
应用扇效应技术探讨共享概念的性质对建构拥有关系情境模型的影响。共包括2个实验,探讨在将“多人买1物”句式中的所购“物品”改变为隐含共同地点信息的“物品”条件下,被试对“多人买1物”拥有行为句式的学习是否表现出扇效应。结果表明,当所购物品隐含的相同地点信息的情况下,“多人买1物”的拥有行为句式无论是否具有明确的地点状语,都如同“1人买多物”的句式一样,没有表现出扇效应,与Radvanskv的研究结果不同。据此认为,只有在共享概念是属于情景模型建构的维度信息的情况下,有共享概念的信息才能整合为同一个情景模型。  相似文献   
145.
"以病人为中心"医疗服务模式的理念与发展   总被引:25,自引:1,他引:24  
纵观20世纪医疗服务的发展历程,医疗服务的发展经历了“以疾病为中心”的传统医疗服务模式到“以病人为中心”的新的医疗服务模式的转变;目前,以“以病人为中心”的医疗服务模式已经成为我国现代医院改革与发展的主题。因此,在阐述医疗服务模式变革与发展的基础上,系统论述了“以病人为中心”的医疗服务模式的内涵与特点,新的理念、新的认识,也带来了新的希望,新的医疗服务模式将不断地改善与提高人们的健康状况与生活质量。  相似文献   
146.
The author first provides her readers with a brief summary of some of Freud's ideas, as found throughout his work, on the notion of 'unconscious'. The notion of unconscious as noun is contrasted to the idea of unconscious as adjective, this latter being proposed as a quality, or a state, ever temporary, dynamic, and subject to the constant changes going on in the individual's internal psychic world, as well as to external conditions. After presenting some considerations, the author then contrasts the Kleinian model of the mind to the Freudian, and Wilfred Bion's contribution is discussed at some length. Within Bion's conception of psychic functioning, the model of 'dream' is highlighted and, in this regard, clarifications are sought regarding Bion's view of the unconscious. To conclude, a brief and superficial approximation to the work of Carl Jung is touched upon, although the author admits to knowing little of Jung's positions.  相似文献   
147.
This study examined preliminary higher-order models relating tripartite dimensions of emotion to severity of anxiety and depressive disorders in 100 clinically referred children and adolescents. In light of the accumulating support for multifactor models of vulnerability and negative emotion in children, the present investigation was designed to establish preliminary estimates of the structure and magnitude of the relations of three emotion factors with dimensions of social anxiety, depression, panic, generalized anxiety, obsessions/compulsions, and separation anxiety. Results were consistent with structures that minimally specified two higher-order emotion factors, yet only some parameter estimates were consistent with theory regarding the tripartite model. Problems with the measurement of tripartite factors and possibilities for further research are outlined.  相似文献   
148.
While the intracarotid amobarbital procedure (IAP) was originally utilized to lateralize speech functions as an aid in the surgical treatment of epilepsy, additional uses for the IAP have emerged including: (1) the use of the IAP to predict post-surgical memory changes, including both global amnesia and smaller, yet significant, material-specific memory deficits; (2) the use of the IAP to provide confirmatory evidence of lateralization of seizure focus; and (3) the use of the IAP to predict post-surgical relief from seizures. While the literature on the IAP is extensive and growing, its utility is marred by the wide variability associated with the procedure itself from epilepsy center to center. This variability renders comparisons among IAP studies problematic and conclusions about IAP efficacy difficult. The variability associated with the amobarbital procedures, as well as the reliability and the validity of the IAP in its nonlanguage uses is reviewed here. A special emphasis is devoted to research conducted in the last decade. Also discussed is the future of the IAP including anticipated research directions.  相似文献   
149.
I first briefly review the dodo bird verdict and suggest that we should be responding to it by looking for a new way to conceptualize how therapy works. Then I describe the dominant medical or treatment model of psychotherapy and how it puts the client in the position of a dependent variable who is operated on by supposedly potent therapeutic techniques. Next I argue that the data do not fit with this model. An alternative model is that the client is the most important common factor and that it is clients' self-healing capacities which make therapy work. I then argue that therapy has two phases—the involvement phase and the learning phase—and that the involvement phase is the most important. I next review the five learning opportunities provided by therapy. Finally, I argue that a relational model of therapy focused on consultation, collaboration, and dialogue is better than a treatment model.  相似文献   
150.
In the bioethical literature, discrimination in insurance on the basis of genetic risk factors detected by genetic testing has been defended and opposed on various ethical grounds. One important argument in favour of the practice is offered by those who believe that it is not possible to distinguish between genetic and non-genetic information, at least not for practical policy purposes such as insurance decision-making. According to the argument from indistinguishability, the use of genetic test information for insurance purposes should be permitted, because genetic test information is no different from non-genetic medical information in any relevant respect, therefore it would be inconsistent to prohibit the former whilst permitting the latter. This paper discusses and defends this argument and suggests a new, more tenable foundation.  相似文献   
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