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181.
选题是计算机化自适应测验(CAT)测试过程的关键环节,选题策略的目标是要达到较高的测量精度,同时也实现试题曝光率控制及其他测验目标的实现.本文根据选题策略的基本原理和衍生发展,将众多CAT选题策略分为五大选题策略系列:Fisher函数系列、K-LI函数系列、α分层系列、贝叶斯系列、b匹配系列;并根据测验目标(测验精度、试题曝光率控制、内容平衡、多条件约束)对这些选题策略进行了细分,并对CAT选题策略的选择思路进行归纳.  相似文献   
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183.
It is widely recognized that abdominal pain and discomfort are common problems in the United States and are often associated with negative quality of life. The prevalence of anxiety/depression elevations and disorders among persons with gastrointestinal disturbances (GI) is estimated to be at least two to three times the rate in the general population. Visceral sensitivity reflects anxiety about GI sensations and its accompanying contexts and often leads to worsening of sensations (e.g. bloating, upset stomach, diarrhea). Among individuals with GI symptoms, visceral sensitivity may be associated with interpreting common sensations as catastrophic which may be related to greater difficulties with emotion dysregulation (e.g. severe anxiety and depression). The current study evaluated the indirect association of visceral sensitivity via emotion dysregulation in relation to depression, anxious arousal, and social anxiety symptoms among 344 young adults with a current history of GI symptoms and problems. Results indicated an indirect effect of visceral sensitivity via emotion dysregulation. These findings provide novel empirical support for the association of visceral sensitivity with emotional distress symptoms among young adults with GI symptoms. Based on the results, targeting emotion dysregulation may be a promising health promotion tactic among young adults with GI symptoms and disorders.  相似文献   
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185.
Collecting samples is a challenging task for face recognition, especially for some real-world applications such as law enhancement and ID card identification, where there is usually single sample per person (SSPS) used to train a face recognition system. To extract discriminative features from the small size samples, in this paper we propose virtual samples via bidirectional feature selection with global and local structure preservation (VS-BFS-GL) to augment the number of training samples. In VS-BFS-GL, bidirectional feature selection is developed, which introduces L2,1 norm to explore the face variations from both horizontal and vertical directions. Further, to include more variations in the virtual images, the global structure information and sample-specified local structure information of the SSPP training set are considered. By integrating bidirectional feature selection, global and local structure, the limited training samples are fully utilized and more knowledge are mined. To further improve the effectiveness of VS-BFS-GL, an auxiliary database containing different face variations can be used to explore the local structure information. We extensively evaluated the proposed approach on AR and FERET database. The promising recognition results demonstrate that VS-BFS-GL is robust to expression, pose and partial occlusion variations in the faces.  相似文献   
186.
This study explored infant feeding practice meanings of HIV-positive mothers. Informants were eight black South African mothers (age range 18–29 years) enrolled in a mother-to-child transmission (MTCT) prevention programme. In-depth interviews on factors that influence exclusive breast-feeding were conducted with the mothers. Thematic analysis of the data yielded meanings around practices of knowledge contestation with health care providers and family, work demands, and personal preferences. Moreover, successful breast-feeding by mothers with HIV status may depend on addressing contradictory messages by health workers on infant feeding and community and family pressure to mix-feed the infant children.  相似文献   
187.
Bioethicists often draw sharp distinctions between hope and states like denial, self-deception, and unrealistic optimism. But what, exactly, is the difference between hope and its more suspect cousins? One common way of drawing the distinction focuses on accuracy of belief about the desired outcome: Hope, though perhaps sometimes misplaced, does not involve inaccuracy in the way that these other states do. Because inaccurate beliefs are thought to compromise informed decision making, bioethicists have considered these states to be ones where intervention is needed either to correct the person’s mental state or to persuade the person to behave differently, or even to deny the person certain options (e.g., another round of chemotherapy). In this article, we argue that it is difficult to determine whether a patient is really in denial, self-deceived, or unrealistically optimistic. Moreover, even when we are confident that beliefs are unrealistic, they are not always as harmful as critics contend. As a result, we need to be more permissive in our approach to patients who we believe are unrealistically optimistic, in denial, or self-deceived—that is, unless patients significantly misunderstand their situation and thus make decisions that are clearly bad for them (especially in light of their own values and goals), we should not intervene by trying to change their mental states or persuade them to behave differently, or by paternalistically denying them certain options (e.g., a risky procedure).  相似文献   
188.
Crisis incidents are volatile situations that can pose significant risk to those involved and to law enforcement. The idiosyncratic conditions that lead to such incidents, as well as their volatility, often militate against consistent explanatory models. However, the application of overarching paradigms, such as the action systems model, has shown some promise in imposing order in the domain. Recent research has successfully differentiated crisis incidents into the four distinct modes of the action systems model: conservative, adaptive, integrative, and expressive. The purpose of this paper is to attempt to replicate this recent study using 242 cases from the United States, Ireland, Canada, and Sweden. Data analysis involves smallest space analyses and constrained multidimensional scaling. Although the results supported the underlying structure of original proposed behavioural model, there are a few deviances. These differences along with the potential influence of cultural variations, offence variable selection, the type of incident, and the sample under scrutiny are discussed. It is evident that there remain several challenges, and further research is required, prior to developing a unified framework.  相似文献   
189.
数能力是数学认知的基本成分。与动物所具有的基本数能力不同,人类不仅具备数量表征能力,更重要的是还拥有对数概念进行表征的数表征能力。虽然具身认知与离身认知都对数概念的表征问题进行了解释,但二者却存在明显理论分歧。具身认知观点主要从具身数量表征和数能力发展的具身认知机制两方面为人类独特数能力的获得提供了理论支撑及实证证据。这启示人们需要重视具身学习在数能力形成实践中的关键作用,重视具身数量表征在数学教学中的作用,仍需进一步揭示其内在的心理和神经基础。  相似文献   
190.
Prior to 2000, personal practice (PP) for therapists mostly meant personal therapy. Recently a new landscape of PPs has emerged, with meditation-based programs and therapy self-practice/self-reflection (SP/SR) programs playing an increasing role in training and personal/professional development. The challenge now for practitioners and researchers is to refocus on the role of PPs in training and professional development. Are PPs of value - or not? Do they have a role in therapist development? How might PPs enhance therapist skilfulness? Do different PPs act in similar or different ways? Currently, the PP literature lacks a theoretical framework to guide practitioners in their choice of PPs or researchers in their choice of research questions and measures. The purpose of this article is to provide such a framework, the Personal Practice (PP) model. The PP model proposes primary impacts of PPs in four domains: personal development/wellbeing, self-awareness, interpersonal beliefs/attitudes/skills and reflective skills. The model also suggests a secondary impact on therapists’ conceptual/technical skills when therapists use reflection to consider the implications of their PP for their “therapist self”. We offer some suggestions to enhance the quality of future research, and conclude that PPs may play an important and perhaps unique role in therapist training.  相似文献   
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