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911.
Existing research on category-based induction has primarily focused on reasoning about blank properties, or predicates that are designed to elicit little prior knowledge. Here, we address reasoning about nonblank properties. We introduce a model of conditional probability that assumes that the conclusion prior probability is revised to the extent warranted by the evidence in the premise. The degree of revision is a function of the relevance of the premise category to the conclusion and the informativeness of the premise statement. An algebraic formulation with no free parameters accurately predicted conditional probabilities for single- and two-premise conditionals (Experiments 1 and 3), as well as problems involving negative evidence (Experiment 2).  相似文献   
912.
This study examined parental behaviors as mediators in links between depressive symptoms in mothers and fathers and child adjustment problems. Participants were 4,184 parents and 6,048 10- to 15-year-olds enrolled in the 1998 and 2000 cycles of the Canadian National Longitudinal Survey of Children and Youth. Mothers and fathers self-reported symptoms of depression at Times 1 and 2 and their children assessed parental nurturance, rejection, and monitoring and self-reported internalizing and externalizing problems and prosocial behavior at Time 2. Hierarchical linear modeling showed evidence of mediation involving all three domains of parental behavior. Findings supported the hypothesis that the quality of the child's rearing environment is one mechanism that carries risk to children of depressed parents. Interventions for parents whose symptoms of depression interfere with parenting responsibilities could help reduce the risk of some childhood disorders.  相似文献   
913.
Although many researchers have documented men's tendency to misperceive women's friendliness as a sign of sexual interest, few have examined individual differences in men's attitudes and past experiences that might predict their likelihood of making these types of misjudgments. We applied an expanded version of Malamuth, Sockloskie, Koss, and Tanaka's (1991) Confluence model to predict frequency of misperception of women's sexual intent with a sample of 356 male college students. Using structural equation modeling, hostile masculinity, impersonal sex, and drinking in dating and sexual situations predicted men's frequency of misperception. Furthermore, the more risk factors men possessed, the more times they misperceived women's sexual intentions. Suggestions are made for theory development and future research incorporating situational as well as personality measures in longitudinal studies.  相似文献   
914.
The authors present a computational model that builds a holographic lexicon representing both word meaning and word order from unsupervised experience with natural language. The model uses simple convolution and superposition mechanisms (cf. B. B. Murdock, 1982) to learn distributed holographic representations for words. The structure of the resulting lexicon can account for empirical data from classic experiments studying semantic typicality, categorization, priming, and semantic constraint in sentence completions. Furthermore, order information can be retrieved from the holographic representations, allowing the model to account for limited word transitions without the need for built-in transition rules. The model demonstrates that a broad range of psychological data can be accounted for directly from the structure of lexical representations learned in this way, without the need for complexity to be built into either the processing mechanisms or the representations. The holographic representations are an appropriate knowledge representation to be used by higher order models of language comprehension, relieving the complexity required at the higher level.  相似文献   
915.
Perhaps the most common criterion for partitioning a data set is the minimization of the within-cluster sums of squared deviation from cluster centroids. Although optimal solution procedures for within-cluster sums of squares (WCSS) partitioning are computationally feasible for small data sets, heuristic procedures are required for most practical applications in the behavioral sciences. We compared the performances of nine prominent heuristic procedures for WCSS partitioning across 324 simulated data sets representative of a broad spectrum of test conditions. Performance comparisons focused on both percentage deviation from the “best-found” WCSS values, as well as recovery of true cluster structure. A real-coded genetic algorithm and variable neighborhood search heuristic were the most effective methods; however, a straightforward two-stage heuristic algorithm, HK-means, also yielded exceptional performance. A follow-up experiment using 13 empirical data sets from the clustering literature generally supported the results of the experiment using simulated data. Our findings have important implications for behavioral science researchers, whose theoretical conclusions could be adversely affected by poor algorithmic performances.  相似文献   
916.
Phantom decoys are alternatives that asymmetrically dominate a targeted alternative and yet lead to increased selection of the target when the decoy is declared to be unavailable. This effect is difficult to explain within most standard theoretical accounts of decoy effects. The current experiments tested between three explanations of this effect: (1) the relative advantage model based on loss aversion, (2) similarity substitution, and (3) range weighting. In Experiment 1, participants were presented trinary choice sets, with half of the sets containing a phantom decoy in one of five possible locations within the attribute space. Phantom decoy effects were robust across all decoy locations but one, and the pattern of effects most closely corresponded to predictions of the relative advantage model. Experiment 2 used a within‐subjects manipulation of the five phantom decoy locations. The overall pattern of effects most closely corresponded to predictions from the relative advantage model, as did the pattern for the group of participants who exhibited the strongest phantom decoy effects. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
917.
918.
Death is an inescapable event. It defines our existence as mortal. It is both a marker of our finitude and a portal to a deeper mystery: what awaits us in, through, and beyond this moment of ending? In thinking about death in the context of a theological dialogue, I identify two key questions: the phenomenological ‘What is death?’ and the philosophical ‘What is the meaning of death?’ as the beginning points of reflection. In general, it is the function of religion to provide some sort of answer to these questions, to give death both coherent definition and adequate understanding. The primary religious response is to articulate appropriate beliefs. But in their intellectual formation and construction, beliefs draw on metaphysics—the structures of logic, language, conceptuality and general worldview presuppositions by which we render all things intelligible and communicable. In this article I shall undertake an exploration of Christian viewpoints on death, which will require noting antecedents and corollaries in Judaism, then discuss possible metaphysical readings of death, that is, philosophical understandings of death that lie within and under, as it were, the otherwise stated religious beliefs about death. The aim of this article is not to present a fully developed ‘theological metaphysics of death’ as such; rather, in the context of an inter-religious dialogical engagement, to raise issues and perspectives from a Christian point of view that might contribute to a wider, more encompassing, theistically oriented understanding of death.  相似文献   
919.
Research is important to validate clinical services, provide information on the effectiveness of practice techniques, and develop the knowledge base of a clinical profession. Genetic counseling students from American Board of Genetic Counseling (ABGC) accredited training programs were surveyed to determine their career research interests and interest in pursuing a hypothetical doctoral degree in genetic counseling. Genetic counseling program directors were surveyed to assess the emphasis on research training within their programs. A substantial number (46%, n = 92) of genetic counseling students are interested in performing research in their careers and many (40%, n = 80) would pursue a doctoral degree in genetic counseling if it was available. Students and directors from programs with a thesis requirement reported a significantly higher emphasis on career research preparation than those from programs without a thesis requirement. The results of this study indicate that future genetic counselors are interested in contributing to the research base that will advance the field. This study suggests a need to strengthen research training within ABGC accredited graduate programs and explore the development of a doctoral degree option in genetic counseling.  相似文献   
920.
We examined the impact of family emotional climate and sibling relationship quality on behavioral problems and adaptation in preschool-aged children. Participants were 63 mothers with a preschool-aged child enrolled in a Southern Arizona Head Start Program. Siblings were identified as children closest in age to target child. Mothers of predominantly Mexican descent (95%) participated in home interviews during the Fall and Spring of the year children entered center-based programs. Sibling relationship quality (warmth, agonism/competition) was proposed to predict children’s adjustment (behavioral problems and adaptation) longitudinally. Results indicate that after controlling for child characteristics (temperament, child gender, birth order) and after accounting for family characteristics (family emotional expressiveness, child exposure to interparental conflict, and parental agreement on childrearing), sibling warmth made a significant and unique contribution to child adjustment as reported by mothers and teachers six months later. Findings are consistent with existing research indicating that sibling relationships impact children’s adjustment and shape young children’s lives in meaningful and marked ways. Moreover, these associations were found with an understudied sample of young children of predominantly Mexican descent in low-income families, and thus make an important contribution to knowledge in the field.  相似文献   
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