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231.
Concise formulas for the standard errors of component loading estimates   总被引:1,自引:0,他引:1  
Concise formulas for the asymptotic standard errors of component loading estimates were derived. The formulas cover the cases of principal component analysis for unstandardized and standardized variables with orthogonal and oblique rotations. The formulas can be used under any distributions for observed variables as long as the asymptotic covariance matrix for sample covariances/correlations is available. The estimated standard errors in numerical examples were shown to be equivalent to those by the methods using information matrices.The author is indebted to anonymous reviewers for the corrections and suggestions on this study, which have led to improvements of earlier versions of this article.  相似文献   
232.
The present paper provides evidence that the processing of verb final clauses proceeds incrementally based on local information that becomes available with each word. The results of three self-paced reading experiments are reported in support of the proposal that NPs in Japanese are associated within clauses before a verb is processed. It is argued that a clause boundary is posited whenever case markers prevent two NPs from being part of the same clause, and slow reading times at the second NP are used as supporting evidence. Moreover, clause boundaries induced by case marking can facilitate processing at later points in the sentence as attested to by faster reading times at relative-clause heads. Contrary to previous findings that argued against a subclass of head-driven parsers, the present results are not easily reconcilable with any type of model that delays parsing decisions until a verb is available in the input sentence.  相似文献   
233.
We investigated crossmodal temporal performance in processing rapid sequential nonlinguistic events in developmentally dyslexic young adults (ages 20-36 years) and an age- and IQ-matched control group in audiotactile, visuotactile, and audiovisual combinations. Two methods were used for estimating 84% correct temporal acuity thresholds: temporal order judgment (TOJ) and temporal processing acuity (TPA). TPA requires phase difference detection: the judgment of simultaneity/nonsimultaneity of brief stimuli in two parallel, spatially separate triplets. The dyslexic readers' average temporal performance was somewhat poorer in all six comparisons; in audiovisual comparisons the group differences were not statistically significant, however. A principal component analysis indicated that temporal acuity and phonological awareness are related in dyslexic readers. The impairment of temporal input processing seems to be a general correlative feature of dyslexia in children and adults, but the overlap in performance between dyslexic and normal readers suggests that it is not a sufficient reason for developmental reading difficulties.  相似文献   
234.
Coney J 《Brain and language》2002,80(3):355-365
Recent neuroimaging studies have revealed neuroanatomical centers of activation that appear to be linked specifically to phonological processes. Furthermore, there is evidence that these centers of activation are more likely to be bilaterally represented in women than in men. However, behavioral evidence of such hemispheric asymmetries or of related sex differences is somewhat inconsistent. Two experiments were carried out to determine whether behavioral correlates of the neuroimaging findings could be demonstrated. The first experiment employed a rhyme-matching task used in a recent neuroimaging study, in which two nonsense words were projected successively to the left or right sides of the visual field. The results indicated that the left hemisphere was superior for this task. An analysis of gender effects, however, revealed that the asymmetry was restricted to men. The second experiment employed a lateralized pseudohomophone detection task that was designed to determine whether the results of the first experiment could be confirmed in the context of a phonological task with a simpler structure. This experiment broadly supported the findings of the first experiment. The results support the specialization of the left hemisphere for phonological processing, and the existence of gender differences with respect to these processes.  相似文献   
235.
The centre of Adorno's Critical Theory is occupied by the theme of happiness. He speaks of the impaired life, of the unjustness of society, of murderous prejudices, of the atrocities in history, of the dissonance in art, of the unhappy consciousness, because something better can only be described from a point of opposition. Happiness cannot be objectified as possession, it always needs to be experienced subjectively, somatically. (With happiness it is like with truth: One does not have it, one is in it.) Happiness cannot be prescribed and ordered; nothing can be done to guarantee happiness. (Happiness goes beyond doing.) Happiness (like fear) has to do with being open to experience which can overwhelm the self. Sexual and aesthetical experience are models for such overwhelming happiness. The sensation of happiness always is very personal, but in this experience the individual leaves its particularity behind. One has to differentiate between goal and object: Happiness may be a goal, but not it itself, only what obstructs it, can be an object of Critical Theory.  相似文献   
236.
Waite TA 《Animal cognition》2002,5(4):209-214
Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice: the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing. To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings are thus consistent with the adaptive-choice model. Electronic Publication  相似文献   
237.
A model of coherentist belief contraction is constructed. The outcome of belief contraction is required to be one of the coherent subsets of the original belief set, and a set of plausible properties is proposed for this set of coherent subsets. The contraction operators obtained in this way are shown to coincide with well-known belief base operations. This connection between coherentist and foundationalist approaches to belief change has important implications for the philosophical interpretation of models of belief change.  相似文献   
238.
In this paper the view is developed that classes should not be understood as individuals, but, rather, as classes as many of individuals. To correlate classes with individuals labelling and colabelling functions are introduced and sets identified with a certain subdomain of the classes on which the labelling and colabelling functions are mutually inverse. A minimal axiomatization of the resulting system is formulated and some of its extensions are related to various systems of set theory, including nonwellfounded set theories.  相似文献   
239.
To be able to learn from experience it is necessary to correctly apprehend experienced feedback and the situation in which it is provided. The results indicate how post-decision consolidation in complex domains may affect learning. The problem may be particularly pertinent in recurrent decision making where considerable risk is involved. The study explores the changes in aspect (signal) importance from pre- to postdiction as a function of outcome information. By postdiction we mean the remembering of an earlier prediction (cf. Hawkins & Hastie, 1990). Subjects were asked to decide on which of four alternative future price developments would follow a historical price trajectory for different commodities, and to rate the importance of each of the chosen alternative's corresponding aspects. The subjects revealed a bias in their support ratings of aspects--seeing support in aspects that traditionally (by themselves and in many contexts) would be seen as neutral or even counter-indicative of the alternative chosen. After an intermission, the subjects were also given information about what was indicated to be the actual development of the market. One group was told that their decisions were correct (irrespective of what the decisions were), another group that they were incorrect but close, a third group that they were incorrect by far, while a fourth group served as a control. Following this information the subjects were again asked to judge the importance of the aspects for their own prior decision on the most likely future development. The results indicated that outcome feed-back had an effect on post decision restructuring of facts. Subjects in the correct condition showed an average consolidation that increased the support, while the wrong conditions lead to negative consolidation (in retrospect indicating that they never found as much support for their decision in the past as they actually did). Thus, in a choice between consolidating their own initial prediction and the price trajectory they would have to live with, the decision makers consolidated the outcome. Therefore, the results of the study were related to the hindsight bias phenomenon (Fischhoff, 1975) and to Kahneman and Miller's (1986) mutability concept.  相似文献   
240.
This study compares the narrative abilities of 13 children with autism, 13 children with developmental delays, and 13 typically developing children matched on language ability. Although groups did not differ in their use of causal language or internal state terms, children with autism and children with developmental delays were less likely than typical children to identify the causes of characters' internal states. Rather, they tended simply to label emotions and explain actions. Children with autism and children with developmental delays also relied on a more restricted range of evaluative devices, which both convey point of view and maintain listener involvement. In addition, the narrative abilities of children with autism were linked to performance on measures of theory of mind and an index of conversational competence, whereas this was not the case among children with developmental delays. Findings are discussed in relation to the social, cognitive, and emotional underpinnings and consequences of narrative activity.  相似文献   
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