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61.
Two hundred and sixty three young adult college students responded to openended questions assessing their specific intentions, motives, and plans for having children. The most commonly stated motives for childbearing reflected a strong interest in establishing an identity and social network. Financial, marital, and emotional stability were identified as important factors influencing the timing of parenthood. Several significant sex differences were found for both motives and the timing of parenthood. These findings are discussed in terms of changing social norms regarding parenthood and changing sex role expectations.Portions of this research were presented at the Eastern Regional Psychological Association Convention in New York, April 1986. This research was funded by a grant from Trenton State College, Committee for Faculty and Institutional Research and Sabbatical Leave. 相似文献
62.
The present study compared two hypotheses about children's solutions to Piaget and Inhelder's (1975) two-set alternative choice probability problems. The first was that children follow rules that specify a temporally ordered sequence of tests and decisions (Siegler, 1981). One prediction of rules is that children who know strategies that combine variables within sets (e.g., ratio or subtraction strategies) will only use them on problems that require such strategies (conflict problems), whereas lower level (nonconflict) problems will be solved by directly comparing the values of variables between sets. The second hypothesis was that once children develop knowledge of within-set solutions to probability problems, they apply them to both conflict and nonconflict problems. The results supported the latter hypothesis. The majority of children who solved conflict problems using within-set strategies explained at least one nonconflict problem by referring to within-set combinations. Results were discussed in terms of their implications for cognitive development and for instruction. 相似文献
63.
Anne M. Zieleniewski D. W. Fulker J. C. DeFries Michele C. LaBuda 《Personality and individual differences》1987,8(6)
DeFries and Fulker (1985) employed a multiple regression analysis of twin data in which a cotwin's score is predicted from the proband's score, the coefficient of relationship (R = 1.0 for monozygotic twins and 0.5 for dizygotic twins), and their interaction to yield direct estimates of heritability (h2) and the proportion of variance due to common or shared environmental influences (c2). The purpose of the report is to extend this model to allow for the analysis of data from more than two familial relationships simultaneously. Data from identical twins, fraternal twins, and siblings pairs, in which one member of each pair was selected based on low reading performance, were analyzed. To analyze the data simultaneously, additional coefficients were added to the regression equation in order to differentiate shared environmental influences of twins and siblings. When the model was applied to the combined cognitive data, significant estimates for heritability were obtained in three of the six tests analyzed. The results also indicated a lack of justification for the separate twin and sibling environmental parameters, and a discussion of more parsimonious models is included. 相似文献
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S. Stefan Soltysik Thomas Nicholas W. Jeffrey Wilson 《Integrative psychological & behavioral science》1984,19(4):169-181
Respiratory rate, respiration amplitude, and vocal responses were recorded in cats of different ages during classic conditioning. Vocal responses to the conditional stimulus (CS) appeared first in 8-week-old kittens, and became prominent at older ages. An increase in respiration rate occurred after the onset of the CS in cats of all ages. Similarly, the decrease of respiration amplitude was observed at all ages, but only in 8-week-old and older subjects did this response resemble an adult pattern. In 4-week-old kittens the response was characterized by an early and brief peak, suggesting an alpha conditional response (CR). Clear and significant discrimination between a warning and a safety signal was present in both respiratory and vocal responses after the age of 8 weeks. 相似文献
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An experiment was conducted aimed first at establishing the reliability and validity of a measure of individual differences in sleeping schedules. Two samples of subjects completed a questionnaire concerning their sleeping behavior which was scored according to the diurnal or nocturnal pattern of their responses. The scores were then used to classify subjects as morning people or evening people. Both the internal reliability and cross-time reliability of the scale were assessed and found to be high. In addition, three indices of construct validity, obtained 4 months after the administration of the scale, supported its validity. In a second part of the experiment, subjects classified as either morning or evening people rated themselves on a set of behavioral and personality dimensions. Another sample of subjects indicated their perceptions of morning people and evening people in general, along the same dimensions. It was found that subjects did have strong beliefs about personality and behavioral differences between morning people and evening people. However, the self-perceptions of the actual morning and evening people did not differ, thereby casting doubt on the validity of popular stereotypic perceptions about the two groups. 相似文献
69.
Dr. Jeffrey M. Halperin Rachel Gittelman Donald F. Klein Rita G. Rudel 《Journal of abnormal child psychology》1984,12(1):1-14
Mixed hyperactive/reading-disabled children, selected from a large sample of hyperactive children, were compared to pure hyperactive children on demographic, behavioral, and neuropsychological measures. Children in the Mixed group were reading-disabled relative to age and IQ; those in the Pure group had achievement scores that were average relative to age and IQ. The Mixed group was significantly older than the Pure group; there were no differences in gender, race, or socioeconomic status. Behaviorally, the groups did not differ significantly on teacher ratings or on psychiatric ratings of aggression. The Mixed group had a significantly higher Performance IQ, whereas the Pure group had a significantly higher Verbal IQ and performed better on measures of cognitive impulsivity. Several other measures failed to distinguish the groups. The data give minimal support to the notion that pure hyperactive and mixed hyperative/reading-disabled children constitute distinct subgroups of Attention Deficit Disorder with Hyperactivity.This research was supported in part by Mental Health Clinical Research Grant MH-30906 and by U. S. Public Health Service Grant MH-18579. 相似文献
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