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81.
    
As a core component of most cognitive diagnosis models, the Q-matrix, or item and attribute association matrix, is typically developed by domain experts, and tends to be subjective. It is critical to validate the Q-matrix empirically because a misspecified Q-matrix could result in erroneous attribute estimation. Most existing Q-matrix validation procedures are developed for dichotomous responses. However, in this paper, we propose a method to empirically detect and correct the misspecifications in the Q-matrix for graded response data based on the sequential generalized deterministic inputs, noisy ‘and’ gate (G-DINA) model. The proposed Q-matrix validation procedure is implemented in a stepwise manner based on the Wald test and an effect size measure. The feasibility of the proposed method is examined using simulation studies. Also, a set of data from the Trends in International Mathematics and Science Study (TIMSS) 2011 mathematics assessment is analysed for illustration.  相似文献   
82.
There is evidence that exposure to negative news is making people feel bad, but not much is known about why this only affects some people or whether this also applies to everyday news exposure. This study examined the direct and indirect effects of daily news exposure on people's affective states. Using ecological momentary assessment (EMA), 63 respondents (24 men and 39 women) reported their news exposure and affective states five times a day for 10 days. In addition, personal relevance of the news and personality characteristics, neuroticism and extraversion, were assessed. Results showed that negative news perceptions were related to more negative affect and less positive affect, and these effects were moderated by personal relevance, but not personality characteristics. The implications of these outcomes are discussed.  相似文献   
83.
    
ABSTRACT

The term “grandparenthood” was first coined by the psychoanalyst P. Redler, to denominate the intrapsychic and interpersonal relationship between grandparents and grandchildren. Grandparenthood involves a specific relationship with specific conflict areas and with its own process of development, named by this author “grandparenthood crisis”. In this phase, grandparents must cope with different experiences of mourning. The joys of becoming a grandparent help compensate for these sorrows. For children, the figure of grandparents evolves during their development and implies different functions across each development stage.

Despite the importance of grandparenthood in the family context, this is a poorly studied topic in Child Psychology. In this paper, we make a review of the scarce literature on this subject, aiming to relate it with the theory of the “Narcissistic scenarios of parenthood” described by Manzano and Palacio (2005). We emphasize the importance not only of the figure of the grandparents in the child’s development, but also the importance of the relation with the grandchild holds for the grandparent in this life stage. We also try to explore the subject of intergenerational transmission.  相似文献   
84.
85.
    
Urie Bronfenbrenner’s groundbreaking work on development in context has made an enduring impact on the field of developmental science. However, translating his theoretical concepts in empirical studies has proved challenging. In this article, we describe a methodological approach—ecological engagement methodology (EEM)—that was designed to operationalize key elements of Bronfenbrenner’s bioecological theory in studies of development in context. In particular, we describe the development of EEM, illustrate the approach using examples from qualitative and quantitative studies of vulnerable youth, provide a brief guide to implementing EEM, and discuss its major strengths and challenges. We conclude that EEM offers a flexible and powerful way to apply Bronfenbrenner’s theoretical propositions in studies of development in context, yielding data that are of high quality; ecologically valid; and relevant to researchers, practitioners, and policymakers.  相似文献   
86.
    
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87.
Empathy: Its ultimate and proximate bases   总被引:22,自引:0,他引:22  
Preston SD  de Waal FB 《The Behavioral and brain sciences》2002,25(1):1-20; discussion 20-71
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88.
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   
89.
Gutiérrez  G.  de Guzmán  I. P.  Martínez  J.  Ojeda-Aciego  M.  Valverde  A. 《Studia Logica》2002,72(1):85-112
The tree-based data structure of -tree for propositional formulas is introduced in an improved and optimised form. The -trees allow a compact representation for negation normal forms as well as for a number of reduction strategies in order to consider only those occurrences of literals which are relevant for the satisfiability of the input formula. These reduction strategies are divided into two subsets (meaning- and satisfiability-preserving transformations) and can be used to decrease the size of a negation normal form A at (at most) quadratic cost. The reduction strategies are aimed at decreasing the number of required branchings and, therefore, these strategies allow to limit the size of the search space for the SAT problem.  相似文献   
90.
Neuronal changes in normal human aging and Alzheimer's disease   总被引:8,自引:0,他引:8  
This article discusses age-related changes in brain weight, total number of cortical neurons, cortical dendrites, spine, and synapse density. The conclusion is that the present outlook is less grim than it was 30 years ago. Age-related reduction appears to be specific to brain region and cortical layer rather than a general feature. In addition, we describe a different pattern of changes that occur in Alzheimer's disease patients. This review concludes that the association cortices in particular are affected in aging and Alzheimer's disease and that the primary visual and somatosensory cortices are relatively spared.  相似文献   
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