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901.
We define a multi-modal version of Computation Tree Logic (ctl) by extending the language with path quantifiers E δ and A δ where δ denotes one of finitely many dimensions, interpreted over Kripke structures with one total relation for each dimension. As expected, the logic is axiomatised by taking a copy of a ctl axiomatisation for each dimension. Completeness is proved by employing the completeness result for ctl to obtain a model along each dimension in turn. We also show that the logic is decidable and that its satisfiability problem is no harder than the corresponding problem for ctl. We then demonstrate how Normative Systems can be conceived as a natural interpretation of such a multi-dimensional ctl logic. Presented by Jacek Malinowski  相似文献   
902.
The clique partitioning problem (CPP) requires the establishment of an equivalence relation for the vertices of a graph such that the sum of the edge costs associated with the relation is minimized. The CPP has important applications for the social sciences because it provides a framework for clustering objects measured on a collection of nominal or ordinal attributes. In such instances, the CPP incorporates edge costs obtained from an aggregation of binary equivalence relations among the attributes. We review existing theory and methods for the CPP and propose two versions of a new neighborhood search algorithm for efficient solution. The first version (NS-R) uses a relocation algorithm in the search for improved solutions, whereas the second (NS-TS) uses an embedded tabu search routine. The new algorithms are compared to simulated annealing (SA) and tabu search (TS) algorithms from the CPP literature. Although the heuristics yielded comparable results for some test problems, the neighborhood search algorithms generally yielded the best performances for large and difficult instances of the CPP.  相似文献   
903.
This article discusses large-scale assessment of change in student achievement and takes the study by Hickendorff, Heiser, Van Putten, and Verhelst (2009) as an example. This study compared the achievement of students in the Netherlands in 1997 and 2004 on written division problems. Based on this comparison, they claim that there is a performance decline in this subdomain of mathematics, and that there is a move from applying the digit-based long division algorithm to a less accurate way of working without writing down anything. In our discussion of this study, we address methodological challenges that come in when investigating long-term trends in student achievements, such as the need for adequate operationalizations, the influence of the time of measurement and the necessity of the comparability of assessments, the effect of the assessment format, and the importance of inclusion relevant covariates in item response models. All these issues matter when assessing change in student achievement.  相似文献   
904.
Response times on test items are easily collected in modern computerized testing. When collecting both (binary) responses and (continuous) response times on test items, it is possible to measure the accuracy and speed of test takers. To study the relationships between these two constructs, the model is extended with a multivariate multilevel regression structure which allows the incorporation of covariates to explain the variance in speed and accuracy between individuals and groups of test takers. A Bayesian approach with Markov chain Monte Carlo (MCMC) computation enables straightforward estimation of all model parameters. Model-specific implementations of a Bayes factor (BF) and deviance information criterium (DIC) for model selection are proposed which are easily calculated as byproducts of the MCMC computation. Both results from simulation studies and real-data examples are given to illustrate several novel analyses possible with this modeling framework. The authors thank Steven Wise, James Madison University, and Pere Joan Ferrando, Universitat Rovira i Virgili, for generously making available their data sets for the empirical examples in this paper.  相似文献   
905.
Violations of social norms can either be evaluated in an absolute or in a gradual fashion depending on whether group goals are represented as minimal or maximal goals. Recent research has shown that absolute versus gradual deviations lead to increased levels of demanded punishment and inclination to exclude the deviant from the respective moral community. In this article, we investigate whether individual differences in orientation towards setting goals in either minimal or maximal terms predict reactions to norm violation. In three studies we found that a dominant minimal goal orientation (MIN) relative to maximal goal orientation (MAX) increased punishment inclinations and social exclusion tendencies towards norm violators. These effects were mediated by affective reaction and proved to be unique goal orientation effects when possible effects of need for closure, intolerance of ambiguity and regulatory focus were controlled for. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
906.
This study investigated the role of auditory selective attention capacities as a possible mediator of the well-established association between verbal short-term memory (STM) and vocabulary development. A total of 47 6- and 7-year-olds were administered verbal immediate serial recall and auditory attention tasks. Both task types probed processing of item and serial order information because recent studies have shown this distinction to be critical when exploring relations between STM and lexical development. Multiple regression and variance partitioning analyses highlighted two variables as determinants of vocabulary development: (a) a serial order processing variable shared by STM order recall and a selective attention task for sequence information and (b) an attentional variable shared by selective attention measures targeting item or sequence information. The current study highlights the need for integrative STM models, accounting for conjoined influences of attentional capacities and serial order processing capacities on STM performance and the establishment of the lexical language network.  相似文献   
907.
This study aims at discovering the essential constituents involved in the experiences of guilt and shame. Guilt concerns a subject’s action or omission of action and has a clear temporal unfolding entailing a moment in which the subject lives in a care-free way. Afterwards, this moment undergoes a reconstruction, in the moment of guilt, which constitutes the moment of negligence. The reconstruction is a comprehensive transformation of one’s attitude with respect to one’s ego; one’s action; the object of guilt and the temporal-existential experience. The main constituents concerning shame are its anchorage in the situation to which it refers; its public side involving the experience of being perceptually objectified; the exclusion of social community; the bodily experience; the revelation of an undesired self; and the genesis of shame in terms of a history of frozen now-ness. The article ends with a comparison between guilt and shame.  相似文献   
908.
The material examined comprised videotaped group sessions in which the participating sexual offenders talked about their crimes and biographies. Out of the available texts four types of narrative formats of biography construction were elaborated: the medical case report, the coming-of-age novel, the vita sexualis and the family drama. Each format includes specific subjective theories about deviant behaviour and sheds light on the diverse defense dynamics. These dynamics could be extracted analyzing various narrative levels, such as the structure of the narration, the self-positioning in the story and the interactions of the group. It was shown how the participants either accepted or rejected responsibility and guilt, which is considered highly relevant for the prognosis. The presented study gives important insight into psychotherapy with sexual offenders.  相似文献   
909.
910.
Previous studies indicated impaired magnocellular (M) and relatively spared parvocellular (P) visual pathway functioning in patients with fragile X syndrome. In this study, we assessed M and P pathways in 22 female fragile X premutation carriers with normal intelligence and in 20 healthy non-carrier controls. Testing procedure included visual contrast sensitivity and vernier threshold measurements. Results revealed that carriers were selectively impaired on tests of M pathways (low spatial/high temporal frequency contrast sensitivity and frequency-doubling vernier), whereas they showed intact performance on P pathway tests. These results suggest that the deficit of the M pathway is an endophenotype of fragile X syndrome.  相似文献   
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