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991.
Perception of faces by 4 budgerigars (Melopsittacus undulatus), a species of small parrot, was studied with a same-different discrimination task. Reaction times were taken as a measure of the similarity between pairs of faces and analyzed with multidimensional scaling to reveal patterns of similarity among the faces. The perception of natural faces was tested to determine which characteristics were perceptually salient. Color, patterns of markings, darkness of the iris, and size of the pupil corresponded to the observed patterns of similarity among the faces. Differences among budgerigar faces were more salient than differences among zebra finch faces, and budgerigar faces were perceptually distinct from the faces of other avian species. The results from these experiments provide a basis for understanding the ways in which these signals function in the coordination of social behaviors.  相似文献   
992.
This study of college women examines the relationship among sex-role attitudes, curriculum choice, and levels of educational and occupational aspirations and expectations. Data for analysis are from a 1977 survey of college students enrolled in home economics and agricultural curriculums in all southern land grant colleges and universities. Results show that sex-role ideology is only weakly associated with curriculum choice but is related to career ambitions for women in sex-typical and sex-atypical areas of study.  相似文献   
993.
994.
995.
Large sample properties of four methods of handling multivariate missing data are compared. The criterion for comparison is how well the loadings from a single factor model can be estimated. It is shown that efficiencies of the methods depend on the pattern or arrangement of missing data, and an evaluation study is used to generate predictive efficiency equations to guide one's choice of an estimating procedure. A simple regression-type estimator is introduced which shows high efficiency relative to the maximum likelihood method over a large range of patterns and covariance matrices.  相似文献   
996.
My aim in this paper is to examine a rational discovery strategy that I call “assimilation”, the attempt to understand a new domain by systematically interpreting the items it contains in terms of an established conceptual structure. The claim that this approach can lead to important new discoveries is illustrated by considering Galileo's attempt to develop a mathematical theory of the strength of materials and his discovery of mountains on the moon.  相似文献   
997.
998.
The present research is an examination of the parameters and correlates of kanashibari, operationally defined as being unable to move upon awakening or before falling asleep. Nonclinical Japanese individuals (N = 720), 34% of whom reported an experience of kanashibari at least once, were administered D. I. Templer's (1970) Death Anxiety Scale, R. Brown's (1990) Locus of Control Scale, and a questionnaire devised by the authors to collect information about kanashibari. The results showed that the kanashibari experience was positively correlated with death anxiety, with being a woman, and with external-other locus of control; this last measure assessed the extent to which these individuals felt that their lives were determined by fate, good luck, or chance.  相似文献   
999.
We review the implications of recent ERP evidence for when and how grammatical gender agreement constrains sentence parsing. In some theories of parsing, gender is assumed to immediately and categorically block gender-incongruent phrase structure alternatives from being pursued. In other theories, the parser initially ignores gender altogether. The ERP evidence we discuss suggests an intermediate position, in which grammatical gender does not immediately block gender-incongruent phrase structures from being considered, but is used to dispose of them shortly thereafter.  相似文献   
1000.
We assessed the immediate effects of two universal, first-grade preventive interventions on the proximal targets of poor achievement, concentration problems, aggression, and shy behaviors, known early risk behaviors for later substance use/abuse, affective disorder, and conduct disorder. The classroom-centered (CC) intervention was designed to reduce these early risk behaviors by enhancing teachers' behavior management and instructional skills, whereas the family-school partnership (FSP) intervention was aimed at improving parent-teacher communication and parental teaching and child behavior management strategies. Over the course of first and second grades, the CC intervention yielded the greatest degree of impact on its proximal targets, whereas the FSP's impact was somewhat less. The effects were influenced by gender and by preintervention levels of risk. Analyses of implementation measures demonstrated that greater fidelity to the intervention protocols was associated with greater impact on behavior ratings and on achievement scores, thus providing some evidence of specificity in the effect of the interventions.  相似文献   
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