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31.
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   
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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   
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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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Twenty of 150 boys living in a residential setting who were emitting high levels of impulsive/aggressive behavior participated in a study of the effectiveness of a cognitive-behavioral group treatment procedure designed to equip them with skills conducive to alternate and more socially appropriate behavior. Treatment involved 13 meetings of 55 minutes duration over a six-week period. The results indicated significant behavioral changes in school regarding: (1) the intensity of physical fighting, (2) the frequency and intensity of verbal fighting, (3) noncompliance, and (4) being in an inappropriate location. These behavioral changes did not generalize beyond the school setting. Significant increases in the number of identified logical consequences of aggressive behavior and in the number of alternative responses to aggressive behavior were observed compared to control boys. The behavioral changes observed in school largely extinguished during the five weeks between the last treatment session and the follow-up observations.  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   
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We test the hypothesis that COVID-19 vaccine hesitancy is attributable to distrustful complacency—an interactive combination of low concern and low trust. Across two studies, 9,695 respondents from different parts of Britain reported their level of concern about COVID-19, trust in the UK government, and intention to accept or refuse the vaccine. Multilevel regression analysis, controlling for geographic area and relevant demographics, confirmed the predicted interactive effect of concern and trust. Across studies, respondents with both low trust and low concern were 10%–22% more vaccine hesitant than respondents with either high trust or high concern, and 26%–29% more hesitant than respondents with both high trust and high concern. Results hold equally among White, Black, and Muslim respondents, consistent with the view that regardless of mean-level differences, a common process underlies vaccine hesitancy, underlining the importance of tackling distrustful complacency both generally and specifically among unvaccinated individuals and populations.  相似文献   
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Code-switching occurs regularly in the input to bilingual children. Yet, the effect of code-switched input on language development is unclear. To test whether word learning would be affected by code-switching, Spanish–English bilingual children (= 45, 19 boys, MeanAge = 5.05 years; ethnicity: 37 Hispanic/Latino, six Non-Hispanic/Latino, two unreported) were taught English-like novel words in two conditions. In the English-only condition, definitions for novel words were provided entirely in English. In the code-switch condition, definitions for novel words were provided in English and Spanish, incorporating code-switches. Children required fewer exposures to retain novel words in the code-switch than the English-only condition and this effect was not moderated by children's language ability or exposure to code-switching, suggesting that code-switched input does not pose word-learning risks to bilingual children, including children with lower levels of language ability.  相似文献   
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