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961.
In this article we show how the universe ofBST,bounded set theory (a modification ofIST which is, briefly, a theory for the family of those sets inIST which are members of standard sets) can be enlarged by definable subclasses of sets (which are not necessarily sest in internal theories likeBST orIST) so that Separation and Replacement are true in the enlargement for all formulas, including those in which the standardness predicate may occur.ThusBST is strong enough to incorporate external sets in the internal universe in a way sufficient to develop topics in nonstandard analysis inaccessible in the framework of a purely internal approach, such as Loeb measures.Presented byRobert Goldblatt  相似文献   
962.
We give a set of postulates for the minimal normal modal logicK + without negation or any kind of implication. The connectives are simply , , , . The postulates (and theorems) are all deducibility statements . The only postulates that might not be obvious are
  相似文献   
963.
Three days prior to the 1993 Australian federal election 54 Australian university students who identified with one of the two major political parties were surveyed regarding their perceptions of media campaign impact on self and others. Results provided evidence of a third-person effect (Davison, 1983) wherein respondents judged others us more influenced by the election campaign than themselves. Consistent with predictions derived from social identity theory and self-categorization theory (e.g. Turner, Hogg, Oakes, Reicher and Wetherell, 1987), political ingroup members were also judged as less injuenced by campaign content than political outgroup members. Respondents who identified strongly with their preferred party judged self and ingroup members as less influenced by campaign content than did other respondents, and showed more evidence of positive intergroup differentiation. At the same time, however, these respondents exaggerated self–ingroup differences, challenging the theoretical assumption that intergroup diferentiation is associated with ingroup assimilation. Judgements of media impact on self and other also depended on the direction of the campaign message. Respondents believed ‘voters in general’ were persuaded in line with the intent of campaign content, while outgroup members were seen to be persuaded by material favouring their own side but to be uninfluenced by counter-attitudinal content. Election propaganda, irrespective of direction, was seen to amplify existing party preferences in self and ingroup members. Hence the relative invulnerability of self to media impact was pronounced when respondents judged the impact of pro-outgroup messages. Results suggest that perceptions of self–other differences in media vulnerability are influenced by the subjectively salient social relationship between self and other, and are governed by motivational needs, such as self-esteem, social-identity, and differentiation from others (cf. Brewer, 1991; Hogs and Abrams, 1993).  相似文献   
964.
TODAM2, a theory of distributed associative memory, shows how item and associative information can be considered special cases of serial-order information. Consequently, it is important to get the right model for serial-order information. Here, we analyze and compare three distributed-memory models for serial-order information that use TODAM’s convolution-correlation formalism. These models are the chaining model, the chunking model, and a new model, the power-set model. The chaining model associates each item with its predecessor; the chunking model uses multiple convolutions andn-grams to form chunks; and the power-set model interassociates all items in a set in a particular way to form a chunk. The models are compared in terms of their performance on seven basic tests of serial-order information—namely, serial recall, backward recall, recall of missing items, sequential probe tests, positional probe tests, serial-to-paired-associate transfer, and item recognition. The strengths and weaknesses of each model are discussed.  相似文献   
965.
Research concerned with how people understand idiomatic expressions has focused primarily on lexicalization, familiarity or literalness. In contrast, this study examined the extent to which comprehending idiomatic phrases in context depends upon the words which make up such phrases. Using reading time as a dependent measure and by substituting idiomatic expressions with phrases which retain the equivalent semantic meaning in context, the role of familiarity and literalness were again investigated. The results lend support to the importance of familiarity in comprehending idiomatic expressions (Schweigert, 1991); however, they raise questions about the extent to which idiomatic phrases are syntactically frozen. The findings provide a platform for considering contemporary theories of idiomatic comprehension and related theories of meaning.  相似文献   
966.
Several current models of human parsing maintain that initial structural decisions are influenced (or tuned) by the listener's or reader's prior contact with language. The precise workings of these models depend upon the grain, or level of detail, at which previous exposures to language are analyzed and used to influence parsing decisions. Some models are premised upon the use of fine-grained records (such as lexical cooccurrence statistics). Others use coarser measures. The present paper considers the viability of models based exclusively on the use of fine-grained lexical records. The results of several studies are reviewed and the evidence suggests that, if they are to account for the data, experience-based parsers must draw upon records or representations that capture statistical regularities beyond the lexical level. This poses problems for several parsing models in the literature.Aspects of this work were supported by ESRC grant No. R0023 4062 to Don Mitchell, by a Spanish Government grant DGICVT No. PB-92-0656-C04-02 to Fernando Cuetos, and by the Belgian National Fonds voor Wetenschappelijk Onderzoek, of which Marc Brysbaert is a Research Associate. We are grateful to Chuck Clifton, Barbara Hemforth, Martin Pickering, Matt Traxler, and an anonymous reviewer-all of whom made helpful comments on an earlier draft of the paper.  相似文献   
967.
To identify reasons for discrepancies between parent and child reports of child/adolescents's psychiatric symptoms, parents and adolescents (51 pairs) were asked to guess what the other would answer to questions from the PC-DISC about the adolescent's psychiatric symptoms, and to explain why they expected disagreement when the answer they provided for the other was different from their own. Adolescents' explanations for expecting (1) parental denial of symptoms the adolescent reported were: the parent was unaware of, forgot about, assumed the adolescent could not have, or trivialized the symptom; and (2) parental report of symptoms the adolescent denied were: the parent misread or exaggerated the adolescent's symptom, had too high expectations for the adolescent's behavior, put a negative label on or did not trust the adolescent. Parents' reasons for expecting their children to (1) deny symptoms the parents reported were: the adolescent did not remember how s/he felt, lied, did not recognize or minimized the importance or frequency of the symptom; and (2) report symptoms the parents denied were: the adolescent lied, exaggerated the importance of or interpreted the symptom differently.Support for this work was provided by National Institute of Drug Abuse grant number DA-05585 (Dr. Cottler, P.I.), and National Institute of Mental Health grants numbers MH-31302 (Dr. R. C. Cloninger, P.I.) and MH-17104 (Dr. Cottler, P.I.).Address all correspondence, including reprint requests, to Michelle Bidaut-Russell, Ph.D, MPH, MPE, Department of Psychiatry, Box 8134, Washington University School of Medicine, 4940 Children's Place, St. Louis, Missouri 63110.  相似文献   
968.
Biased attention in childhood Anxiety disorders: A preliminary study   总被引:7,自引:0,他引:7  
This study provides preliminary tests of two hypotheses: (1) Anxiety-disordered children show an attentional bias toward emotionally threatening stimuli, and (2) normal controls show an attentional bias away from emotionally threatening stimuli. Twelve children, 9 to 14 years of age, with primary diagnoses of anxiety disorder were compared with 12 normal controls matched for age, gender, vocabulary level, and reading ability. Subjects completed a reaction time task that measured visual attention toward threatening versus neutral words. The anxious group showed the predicted attentional bias toward threat words. However, controls did not show the predicted bias away from threat words. These results are the first showing that biased attentional processing occurs among clinically anxious children. The potential role of such an attentional bias in childhood anxiety disorders and future direction for research are discussed.This research was supported by a Seed Grant and a Small Grant to the first author from The Ohio State University. Portions of this paper were presented at the 27th Annual Convention of the Association for the Advancement of Behavior Therapy, Atlanta, November 1993. Thanks are extended to the participants and all those who helped with the project.  相似文献   
969.
970.
It has been established through several decades of research that children's home environments significantly influence their development. Many researchers have also been interested in expanding research beyond indirect measures of the home environment, such as socioeconomic status, to help understand the nature of specific environmental mechanisms which influence early behavior and cognitive development. The Home Observation for Measurement of the Environment (HOME) Inventory was developed to meet these needs. Specifically, HOME measures the quality of stimulation in a child's early family environment. Almost all studies of the approach's reliability and validity have been conducted with US samples. HOME is, however, being used in other countries. The authors report their findings from a study of whether the psychometric properties of HOME based upon US samples parallel those found in Costa Rica, and whether HOME discriminates between Costa Rican environments with different associations to child health and development. Focus centers upon the infant/toddler version of the HOME Inventory. HOME data for 183 healthy Costa Rican infants were compared to the original HOME standardization sample from Little Rock, Arkansas. The study found the HOME Inventory to be helpful in identifying children at risk for delayed development in this Latin American sample. Lower HOME scores related to a shorter duration of breastfeeding and differentiated children with iron deficiency anemia in infancy, a condition associated with long-lasting developmental disadvantage.  相似文献   
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